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Honors Physics – Final Exam Review, Exam Format and Exam Outline
Format of Exam
Section 1: 40 Multiple Choice questions (1 point each).
Section 2: 6 Free Response problems (10 points each)
Suggestions for Studying
Review all the previous tests and identify what areas need improvement.
Review previous assignments and simulations
Any topics about which you still have a lot of confusion, go back to your notes, APlus Physics web, the
physics classroom review problems, course book, your notes etc and review thoroughly.
Complete all practice problems/assignments and compare your answers with other students. (Teacher-
generated answers will not be provided – so work together to uncover the answers. The process of
collaborating with others is critically important to your learning).
What to bring to the exam
Your AP-Physics Equation sheet
Calculator with fresh batteries (or extra batteries)
2-3 pencils and erasers
A sense that you’ve prepared yourself for the exam
Final Exam Review
A. Math Review for Physicists
Vocabulary: accuracy, precision, linear, exponential, inverse, root curve, dimensions, independent variable,
dependent variable
1. Triangles: hypopp /sin , hypadj /cos , adjopp /tan , Pythagorean theorem: a2 + b
2 = c
2
2. Significant Figures
a. Sig figs with addition/subtraction (fewest decimal places)
b. Sig figs with multiplication/division (fewest sig figs in any of the factors)
3. Units/Unit Conversion
a) The MKS (meter-kilogram-second) system is also known as the SI system.
Base units: meters, kilograms, seconds, Amperes
b) Derived units are combinations of base units for example: m/s,
Newton (kgm/s2), Joule (Nm), Watt (J/s)…
i. Practice: Express the following in terms of base units. (Hint: Use equations.)
1. Newtons
2. Joules
3. Watts
c) Conversions (giga, mega, kilo, hecta, deka, deci, centi, milli, micro, nano, pico)
You should be able to convert between units using conversion factors.
i. Convert 100mg to kg (ans=1x10-4
kg)(hint: convert mg to g, then g to kg)
ii. convert 1000MeV’s to Joules: (ans=1.6x10-10
J)
a. Dimensional consistency (check to see if the units in an equation “work”)
4. Linear Relationships
a. Slopes/intercepts
b. Meaning of the slope
c. Writing equation from a linear graph
d. Using the equation to answer questions about the data
5. Graph Shapes (recognize shapes)
a. Linear: y = kx + b
b. Exponential: y = kxn + b
c. Inverse: y = kx-n
+ b
d. Root
6. Graphing (Plotting Graphs from data)
a) Always start the axes at (0,0)
b) Use a consistent scale, i.e., make each box worth the same amount.
c) Never use “breaks” on either axis.
d) Never connect the dots with line segments.
iii. Draw the best-fit straight line with a straight edge if the data is practically linear. (y=kx)
iv. Draw the best fit smooth curve for non-linear data (usually parabola (y=kx2) or hyperbola
(y=k/x), or inverse-square which also looks like a hyperbola y=k/x2).
v. Practice: State and sketch the shape of the following graphs. Choose from straight line,
parabola or hyperbola:
1. Force on spring vs. change in length: _________________
2. D vs. t for accelerated motion: _________________
7. Experimental Conditions
a. Independent on the x-axis and dependent variables on the y-axis.
b. Recognize which variables are held constant
8. Vectors vs. Scalars
a) Vectors have both magnitude (amount) and direction while scalars have only magnitude.
b) If you can draw the quantity with an arrow, it is a vector. Examples are: force, velocity and
momentum. Scalars are not drawn. Some scalars are mass, energy, and power.
c) Speed is a scalar, but speed with direction is a vector called velocity.
d) Distance is to displacement as speed is to velocity.
e) When adding vectors like forces or velocities, arrange them head to tail without rotating them.
f) Practice: Add the following vectors head to tail roughly to scale, and draw the resultant:
vi. Vx=10m/s + Vy=20m/s
vii. D1=100m Northeast plus D2=200m South.
viii. Fx=100N plus Fy=-100N
g) To get the components of a vector, e.g. velocity, use Vx=Vcos(angle) for the adjacent side, and
Vy=Vsin(angle) for the side opposite the angle.
Mechanics 2: Position, Velocity and Acceleration
Vocabulary: vector, scalar, position, distance, displacement, speed, velocity, strobe diagram, motion map,
frame of reference, average velocity, instantaneous velocity, average acceleration, instantaneous
acceleration
1. Motion diagrams and motion graphs
a. How to draw and interpret them
b. Frame of reference
2. x vs. t, v vs. t, a vs. t graphs
a. finding equation that describes a linear graph
b. converting among graphs
c. converting between graphs and verbal descriptions
d. converting between graphs and strobe diagrams/motion maps
e. slope of x vs. t curve = instantaneous velocity
f. slope of v vs. t curve = instantaneous acceleration
g.
h.
3. Comparing motion of two objects graphically
4. t
xv
,
t
va
5. Vectors (displacement, velocity, acceleration, force, momentum) and scalars (distance, speed) Conceptual Examples and describing motion:
Acceleration:
a. ..is the amount that velocity changes by every second. So, an acceleration of 4m/s2 means an
object is speeding up by___________( 4m/s) each second.
b. If an object has a velocity of +100m/s, and accelerates at -10m/s/s, it is slowing down by
________(10m/s) each second. If it maintains that acceleration for longer than 10s, it reverses at
t= ? s (10s) and then speeds up in the NEGATIVE DIRECTION by _____(10m/s/s.)
c. A ball thrown vertically upward at 40m/s with g=-10m/s/s, would reach the peak at t=
_________, then return to its starting position with a velocity of -40m/s after a total time of
_____________.
(ans: 4,8)
d. Motion graphs: You should be able to graph position, velocity and acceleration vs. time for
constant acceleration and constant velocity.
e. If velocity is constant, predict or sketch what the graphs would look
like_________________________ (The position graph is a diagonal line, velocity graph is flat
and acceleration is zero.)
f. If acceleration is constant and forward, …think….(the position graph will be ______?
(parabolic, concave up). The velocity graph is __________? (a diagonal line) and the
acceleration graph is_?_________ (flat.)
Mechanics 3: One Dimensional Kinematics (constant acceleration)
Vocabulary: freefall, kinematics
1. Stacks of kinematics curves
2. Equations
a. tvvx fi 2
1
b. 22
1 tatvx i
c. xavv if 222
3. g = 9.8 m/s2 downward (any object in the air on earth has an acceleration of g!)
4. Describe x, v, and a for an object tossed straight up into the air
Two Dimensional Kinematics (motion in two dimensions!)
Mechanics 4 – Projectile Motion
Vocabulary: projectile, trajectory, horizontal component, vertical component, range, hang time/flight time,
frame of reference, air resistance, apogee, perigee
1. Projectile: any object on which gravity is the only force
2. Acceleration of a projectile (on Earth) is always g (9.8 m/s2)
3. Divide problem into horizontal and vertical parts
a. Horizontal
i. Horizontal component of velocity is always constant (a = 0)
ii. t
xv
b. Vertical
i. Vertical acceleration is always = g
ii. All equations from last unit apply, and acceleration = g: 2
21 tgtvy i and
ygvv if 222
c. Any given quantity that is neither horizontal nor vertical must be resolved into its components (
use Vx= Vcosine angle anv Vy = V sine of angle).
4. For a projectile launched horizontally, flight time depends only on the height from which it was
launched
5. For projectiles launched at angles: REMEMBER TO RESOLVE THE INITIAL VELOCITY INTO
COMPONENTS!!
6. Effect of air resistance on trajectory
7. Satellite Motion
NOTE: when solving Projectile motion problems, make work easier for you by remembering the
following:
a) Keep horizontal (x) and vertical (y) quantities SEPARATE!! Make an x-y chart and never mix
these quantities in the same equation. The only exception is if you know the final Vx and Vy, and
you need the resultant final V. Then you use Vx and Vy in the Pythagorean theorem.
b) If a projectile is launched horizontally, Vyi=0.
c) If a projectile is launched at an angle, get Vx as Vcosine angle and Vyi as Vsine angle.
d) You are free to choose the pos/neg directions, but usually up is taken as positive and down is
negative. If a ball was thrown upward, but is now on the way back down, the displacement is
positive because the ball is above the start point, but the velocity is negative because it is moving
downward.
e) In the X-direction, use only dx=vxt (distance = speed times time) since (acceleration ax =0 so no
other kinematic equations work.)
f) Use the Y-direction to find time, then use dx=vxt to find the horizontal distance, or “range” of the
projectile.
g) Practice This Problem:
ix. A ball is kicked from ground level with a velocity of 20m/s at 30 degrees above
horizontal. Determine the horizontal displacement as it lands: (t=2s, dx=34m)
x. Determine how high the ball went: (t=1s, dy max = 5m)
Mechanics 5 – Circular Motion and Centripetal Force
1. Vocabulary: uniform circular motion, circumference, tangential/linear velocity, centripetal acceleration,
centripetal force, centrifugal forc
2. Circular Motion
a. During circular motion, the net force and acceleration are toward the center. That means they are
“centripetal”.
b. The centripetal force could be tension if swinging a mass in a circle at the end of a string. It
could be gravity (satellites) or it could be friction (car around track).
c. Centripetal vs. centrifugal force and Newton’s 1st Law
d. T
rv
2 , where T is the period
e. r
vaC
2
, r
mvFC
2
( Use Fc=mac = mv2/r to explain physis problems, for example, If r doubles what happens to
F? a? (both halved) If v doubles, what happens to F? a? (both quadruple). If m doubles with
no change in r or v? (a=no change, F=doubles))
f. Centripetal force is a net force!
g. You should be able to Identify centripetal forces on different objects (gravity, tension, friction
(unbanked curve), friction & normal force (banked curve), etc). You should be able to solve for
apparent force (normal force) e.g. in tne elevator problesm and rollercoater ( amusement park0
h. Remember Nf FF
i. For Circular Motion of planets, Centripetal Force is provided by the Newton’s Law of Universal
Gravitation: Fc= 2
21
r
mGmFg
Mechanics 7 – Forces
Vocabulary: Force, inertia, agent, object, net force, terminal velocity, equilibrium, contact force, field force,
force of gravity, normal force, force of static friction, force of kinetic friction
1. Newton’s Laws of Motion
a. Inertia
b. Fnet = ma
c. Equal and opposite force pairs (agent/object notation)
d. Universal Law of Gravity
Examples/Concepts:
2. Newton’s First Law
a. An object’s velocity will not change unless and unbalanced force makes it change. This is
known as Newton’s first law, the law of inertia.
b. Example 1: A car traveling at constant velocity. Which force is greater – the force of traction
making it go forward, or the force of friction resisting? They are EQUAL!! If they weren’t the
velocity would change. More traction force means going faster, more friction means slowing
down.
c. Example 2: A bullet fired in outer space (no gravity) will continue in a straight line at constant
speed until it hits something.
Also, in a head on car crash, passengers without seatbelts tend to go forward into the window
because they are objects in motion who tend to stay in motion. Wear your seatbelt!!
d. Inertia is measure by mass. Which has more inertia: a train at rest or you on a bike at top speed?
It is the train. It has more mass and is hard to get moving.
3. Newton’s Second Law
a. Fnet=ma. This means if there is a net (unbalanced) force there will be an acceleration (change in
velocity).
b. Practice: If the forward force on an 8kg object is 12N, and the opposing force is 8N,
determine the net force and acceleration. (4,.5)
c. Practice: If a 100N object is in freefall, and there is a 40N drag force, what is the
acceleration? (100N-40N=10kg(a) so a=6m/s/s)
d. You also need to be able to draw force diagrams. Practice with a mass on an incline with
friction, then a mass hanging from a clothesline. Look them up in the two texts books (blue and
the red book), physics classroom and Aplus physics website if you are not an expert!
e. Remember that the coefficients of friction depend only on the type of surfaces, and NOT on the
surface area in contact. Kinetic=sliding, static=no sliding.
4. Newton’s 3rd
Law is the law of action-reaction. Whenever any two bodies interact they ALWAYS
apply equal and opposite forces to each other. This includes the earth and you (gravity), a brick
breaking a window, a bullet fired from a gun, a baseball bat hitting a ball,…)
5. The Law of Universal Gravitation
a. If two planets move twice as far apart, what happens to the force of gravity they apply to
each other? (Of course it would be quartered since the law of universal gravitation is an
inverse square law)
b. If the masses of two stars both are halved, what happens to the force of gravity between
them? Same answer (quartered) since both m’s are in the numerator.
c. Where does gravity’s strength rank among the 4 natural forces? The four forces are gravity,
electromagnetic, strong nuclear and weak nuclear. Gravity is by far the weakest of these.
(Gravity-Weak-EM-Strong)
6. Types of forces
a. Applied, tension, kinetic friction, static friction, air resistance, normal, buoyant
b. Gravitational, electric, magnetic
7. Free-body diagrams
a. Draw them
b. Calculate individual forces
c. Calculate net force
d. Objects on flat ground or on an incline
8. Equilibrium Forces
a. Find unknown force when Fnet = 0
b. Find force that will make Fnet = 0
9. Force of friction
a. Kinetic and static friction
b. Ff = µFN
10. Torque
a. Torque = perpendicular force x lever arm
b. Formula: Torque = F┴∙d
11. Kinematics of rotational motion (or angular motion): replace linear variables with angular
displacement theta, angular velocity omega and angular acceleration alpha.
Linear Momentum (P) and Impulse (J)
Mechanics 6 – Momentum and Impulse
Vocabulary: inertia, momentum, elastic, inelastic, impulse
1. Remember: Inertia
2. Momentum
Takes into account both inertia (mass) and velocity
p = mv
Momentum is a vector
Units: kg∙m/s
3. Conservation of Momentum (P).
Total momentum is always conserved (The most unbreakable law in the universe!)
Momentum is conserved in all collisions and recoils, and when two bodies pull together with a
spring or gravity.
Usually the system is at rest either before or after the collision/recoil which means the total
momentum is ZERO and the 2 bodies have EQUAL and OPPOSITE momentums.
For more complicated problems, use m1v1i + m2v2i = m1v1f + m2v2f (not on reference table.)
In any collision, Force of impulse, change in momentum and collision time is the same for both
objects.
For the system as a whole : pinitial = pfinal
4. To solve momentum problems:
Define an initial state and a final state
Write an equation for the initial momentum
Write an equation for the final momentum
Set them equal and solve pinitial = pfinal
5. Elastic (“bouncing”) and Inelastic (“sticking”) Collisions
6. Impulse and Momentum
Impulse is a change in momentum. is not on the reference table either. Set to
solve most impulse problems.
The area under an F-t graph is impulse..
F*t = m*v = p
For impulse calculations where the force is changing, use the average force times change in time
Practical applications for impulse=change in momentum are (bat and ball, car airbags,
gymnastics mats, safety nets, safety belts, car crashes, jackhammer, catching an egg without
breaking it)
7. Newton’s Second Law for Rotation: Net Torque= Moment of Inertia (I) * Angular Acceleration.
[1] Moment of Inertia (I) = Mass * Square of Lever Arm (distance) from axis of rotation (MR2)
[2] Angular Momentum L
[3] The law of conservation of Angular momentum (examples: ice skaters, marry-go-round, amusement
park, spinning gyroscope, gymnastics etc
Mechanics 7: – Work and Energy
Vocabulary: Energy, work, power, kinetic, gravitational potential, elastic potential, spring constant, internal energy,
conservative force, heat, thermal equilibrium, specific heat, entropy
1. Energy
a. the ability of an object to produce change in itself or its environment
b. unit – Joule (J) = Nm
2. Ways to represent energy
a. Energy pie charts
b. Energy flow diagrams
c. Energy bar graphs
3. Forms of Energy Storage
a. Kinetic Energy – Is the object moving?
i. KE = ½ mv2
ii. KE is a scalar (technically depends on speed, not velocity)
iii. translational and rotational KE
iv. KE is conserved in elastic collisions, but not in inelastic collisions
b. Gravitational Potential Energy – Is the object some distance above the ground (or other reference
point)?
i. GPE = mgh
ii. Must pick a reference point
c. Elastic Potential Energy (EPE) – Is there a spring or other elastic object that is either stretched or
compressed?
i. Work Done By Spring=EPE = ½ kx2
ii. x is the displacement from rest (non-stretched or compressed) position
iii. Change in EPE = EPEf - EPEi
iv. F = kx (Hooke’s Law – force needed to stretch/compress a spring (Named after Dr. Robert
Hooke))
d. Chemical Energy – Energy stored in chemical bonds
e. Internal (Thermal) Energy – Is there friction or some type of collision/compression?
4. Methods of Energy Transfer
a. Working – It’s working if there is a change in energy and it’s not either of the other two!
b. Heating – Change in temperature
c. Radiating – emitting electromagnetic waves
Mechanics 8: Work and Power
d) Work is the energy given to an object. We use W to stand for potential or kinetic energy in equations
like electric potential V =W (work) / charge (q) and W=Pt. (power * time)
e) Work = Fd. The force and displacement must be IN THE SAME DIRECTION when using this
equation. Work is positive if F and D are in the same direction, or negative if F and d are opposite
each other.
f) SI Unit of Work is Joule (J) Named After James Joules
g) Practice: While carrying a pizza at constant speed you are NOT doing work on the pizza since your
force is UP but displacement is FORWARD. Also, the pizza gained no PE since it didn’t go higher,
and didn’t gain KE since it didn’t go faster.
h) The area under what type of graph would equal the work done?
(F vs. d)
i) Practice: If you are using a pulley and do 100J of work to lift a 10N box 8m higher (80J of PE),
how much work was done against friction? (20J)
j) Power is not how much work is done, but how FAST. Power is the RATE at which energy is
produced/delivered. P=Fv gives you the average power if you use average velocity, and instantaneous
power if you use the velocity at that instant.
5. Work is a change in energy (Work = Change in Energy)
a. Work= Change in Energy = Force (F) * distance (x)
b. W is + if energy is put into the system
c. W is – if energy is removed from the system
6. Power
a. The rate at which energy is transferred
b. Unit – Watt (W) = J/s. Watt is named after James Watt.
c. t
E
t
WP
d. At any instant, Power = Force (F) * Velocity (V)
7. Conservative and Non-conservative forces
a. Conservative – energy transfer is reversible; Change Energy or Work done depends only on the initial
and final positions. Work does not depend on path e.g. work done by gravity or spring force or
electromagnetic force.
b. Non-conservative – energy transfer is not reversible; Work or Change in Energy depends on the total
distance traveled (example is Friction)
2. Conservation of Energy
a) When a system is allowed to move on its own – no engine, no applied force – you will want to use
conservation of energy: Total Initial Energy ETi = Total Final Energy ETf.
b) ET means total energy – the total amount stays constant just changes forms. ET includes KE, PE and
Q (heat or work done by friction) when friction is present.
c) Work done against friction can be calculated with Wf=Ffd
d) PE can be gravitational, (PE=mgh) or in a spring (PE=1/2kx2.)
Electricity and Magnetism
Vocabulary: insulator, conductor, semiconductor, conduction, induction, electric potential difference, series,
parallel,
paramagnetic, diamagnetic, ferromagnetic, motor, generator
1. Electrostatics
a. Electric Charge and Charge Transfer
Properties of charge (likes/unlikes, conserved, quantized)
SI Unit of charge is Coulomb (C), named after Augustine Coulomb
Insulators/Conductors/Semiconductors
Charging by conduction/induction
Induced charge separation (conductor)/polarization (insulator)
b. Coulomb’s Law
F = kq1q2/r2
Electric force is a field force, generally stronger than gravity
Apply to two charges or multiple charges
c. Electric Field Lines
away from +, toward –
The term positive and negative charges were assigned by Benjamin Franklin
closer lines stronger field
direction of field at a point is the tangent to the field line at that point
d. Electric Potential Difference
Volt = J/C
V = W/q
V = Ed
The SI Unit of potential difference (voltage) is Volt, named after Alessandro Volta.
e. Parallel Plates and Capacitors
Electric Field is uniform between parallel plates
Capacitance (C) = Charge (Q) / Voltage (V)
Units of capacitance is Farad; named after Michael Faraday
Capacitor stores electrical energy in the electric field between the plates
Capacitance of parallel plates = * Area / distance
2. Electric Current
a. I = change Q/ change time t (Units: Ampere = C/s; Named after Andre Marie Ampere)
b. Conditions for Current Flow
Electric potential difference
Closed path
c. Direct Current Circuits
Schematic Circuit Symbols
Ohm’s Law: V = IR
SI Unit of resistance is Ohm, named after Georg Simon Ohm
Series Circuits: I is same everywhere
VT = V1 + V2 + V3 + …
RT = R1 + R2 + R3 + …
i. Ammeters connect in series so current flows through it.
ii. Voltmeters are connected across an element in parallel to measure the potential
DIFFERENCE between two different points.
iii. If one resistor is removed the current stops, everything turns off.
e) Parallel Circuits
i. The currents in each branch add up to the total current.
ii. Each resistor is connected independently to the power source.
iii. If one resistor is removed the others operate the same, unchanged.
iv. Don’t forget the FLIP when using the 1/R equation!
IT = I1 + I2 + I3 + …
V is same everywhere
1/RT = 1/R1 + 1/R2 + 1/R3 + …
Complex Circuits – simplify
d. Power
P = IV = I2R (unit: Watt)
Energy dissipated by a circuit element: E = Power * time t
Units of energy (J, kWh)
3. Magnetism
a. Different from electric force – can attract and repel; magnetic poles cannot be isolated
b. Magnetism basics
Magnetic field produced by a moving electric charge or current.
Magnetic domains
c. Magnetic Fields
Away from North, towards South and don’t cross
Always complete circles (because poles can’t be isolated)
Created by current carrying wires (right-hand rule, curved fingers)
Magnetic fields are created by moving charges, usually electrons.
Domains are areas where electrons in iron spin the same way. When you put a magnet to a
piece of iron, the domains align and the iron is temporarily magnetized.
The earth’s “north pole” is really a magnetic south. Obviously, since the N pole of compass is
attracted to it, and opposites attract
d. Force on a charged particle in a magnetic field
Right-hand rule, open fingers
Magnetic Force (F) on a charge (q) moving with a velocity V in a magnetic field B is given
by F = qvB
Charged particle in a magnetic field travels in circular path
e. Force on a current-carrying wire in a magnetic field (right-hand rule, open fingers)
f. DC Motors and Generators (review the last phet simulation assignment on electromagnetism/faraday
law)
Motors: How they work
Generators: V = Blv (induced potential difference = mag field strength x length of conductor
in field x velocity of conductor)
f) Field strength is a.k.a. “flux density”. Measured in Teslas (named after Nicola Tesla) and is
(Weber/m2)
g) Webers (named after Wilhelm Waber the unit for the total # of magnetic field lines.
h) Michael Faraday’s Law: of Electromagnetic Induction. When magnetic field changes ( current is
produced in a wire and light bulb produces light)
i) Moving charge could experience force due to both magnetic field and electric field.
j) Moving charge produces both magnetic and electric field.
.
Sample Free Response Questions
WARNING! This is only a guide in order to focus your studying effort. The final will not be exactly like this. If it
was, it would only be measuring your powers of memorization, and I despise that. The problems presented here
approximate those on the final; they do not mimic them. Some problems have solutions, some do not. Please study
over and above that which is given here.
SAMPLE FRQ: Linear Momentum
A 0.040-kg dart is shot from a 2.60-kg rifle at a speed of 45 m/s. It strikes and sticks into a 0.630-kg block at rest on
a level surface.
a) What is the recoil speed of the rifle?
b) What is the speed of the block after the collision?
c) What is the loss in kinetic energy in the dart/block collision?
d) If the coefficient of friction is 0.45, how far does the block slide before coming to rest?
e) If the dart bounced off of the block in a perfectly elastic, head-on collision, instead of sticking into it, what
would be the final speed of the block?
f) In part (e), what is the loss of kinetic energy? Explain.
EXAMPLE PROBLEMS
1. A mass of 1.5 kg moves in a circle of radius 25 cm at 2.0 rev/s. Calculate the required centripetal force for the
motion.
2. A car moving at 5.0 m/s tries to round a flat corner that has a radius of curvature of 8.0 m. How large must the
coefficient of friction be between the wheels and the roadway for the car not to skid?
3. A pilot attempts a vertical loop during an air show. While upside-down at the top of the 245-meter radius loop
he experiences a g-force of 2.75 g’s. Calculate the speed of the plane at this point.
4. How much would a German shepherd of mass 34.0 kg weigh on earth? How much would it weigh on Uranus?
[massUr = 8.80 x 1025
kg radiusUr = 2.67 x 107 m]
7. A 60.0-kg woman walks up a flight of stairs that connects two floors 3.00 m apart. (a) How much lifting work
is done? (b) By how much does the woman's gravitational potential energy change?
8. A 1200.-kg car sliding out of control along an icy (frictionless) road at 20.0 m/s travels up an equally icy hill.
What is the greatest height reached by the car?
9. (referring to the last question) If the road and hill were not completely frictionless and the car reached a height
of 15.0 m before coming to rest, how much work was done on the car by friction during its slide?
10. A 2.50-kg block slides down a frictionless incline, across a level frictionless floor and compresses an ideal
spring. (k = 120. N/m) If the box originally began its journey from a height of 1.25 m above the floor,
calculate (a) its speed at the bottom of the incline, (b) the maximum compression of the spring, and (c) the
speed of the box when it is at a height of 0.350 m above the ground.
11. Calculate the average horsepower required to raise a 150.-kg drum to a height of 20.0 m in a time of 1.00
minute.
12. A 40000.-kg freight car is coasting at a speed of 5.00 m/s along a straight track when it strikes a 30000.-kg
stationary freight car and couples to it. What will be their combined velocity after impact?
13. Two bodies of masses 8.00 kg and 4.00 kg move along the x-axis in opposite directions with velocities of
+11.0 m/s and -7.00 m/s, respectively. They collide, and the 8.00-kg mass moves at + 1.00 m/s. (a) Find the
velocity of the 4.00-kg mass. (b) Identify the type of collision.
14. A 2.00-kg block of wood rests on a tabletop. A 5.00-g bullet moving horizontally with a speed of 155 m/s is
shot into the block, sticking in it. The block then slides along the table, stopping in 0.750 s. (a) Find the speed
of the block just after impact, and (b) the frictional force between the block and the table.
15. A hand grenade of mass 0.600 kg explodes into three pieces. a 0.400-kg piece moves at 155 m/s north and a
0.125-kg piece moves at 225 m/s west. Find the velocity of the third fragment.
ANSWERS:
1) 59 N
2) 0.31
3) 94.9 m/s
4) 333 N , 280. N
5) 0.332 Hz
6) 1.54 s
7) a. 1760 J b. 1760 J
8) 20.4 m
9) -63600 J
10) a. 4.95 m/s b. 0.714 m c. 4.20 m/s
11) 0.657 hp
12) +2.86 m/s
13) +13.0 m/s
14) a. 0.387 m/s b. 1.03 N
15) 908 m/s, 66 S of E
SAMPLE CONCEPTUAL/FREE RESPONSE QUESTIONS: ELECTRICITY AND MAGNETISM
1. How are positive ions formed? How are negative ions formed?
2. What is the fundamental rule regarding charge interactions?
3. Can charges be created or destroyed?
4. How are conductors different from insulators?
5. Explain how charges can be moved by:
a. conduction:
c. induction:
d. friction:
grounding:
6. What happens to the electrical force experienced by two charged particles separated by some distance if:
a. one of the charges doubles?
b. both charges double?
c. the distance is doubled?
d. the distance is tripled?
e. one of the charges doubles and the distance is doubled?
7. Draw electric fields for the following:
a. weak positive charge b. strong negative charge
HONORS PHYSICS ,FINAL EXAM REVIEW – May 2016
7. c. two positive charges d. a negative charge and a positive charge
8. Explain how each of the following factors affects resistance through a wire:
a. conductivity:
b. thickness:
c. length:
d. temperature:
9. What are the relationships between current and voltage and current and resistance according to Ohm’s Law?
10. What relationship do current and resistance have?
11. If you increase the resistance, what happens to the current? If you decrease the resistance,
what happens to the current?
11. Do you buy electrons from the power company?
12. What are two safety devices used in circuits? How do they work?
13. What is the difference between direct current and alternating current?
14. What is a source of direct current? of alternating current?
15. How much current flows in a 175 resistor when a voltage of 5.0 V is across it?
16. What is the resistance of a cold incandescent bulb filament if it draws a current of 0.43 A
when plugged into a 120 V circuit?
17. What is the resistance of an electric frying pan which draws 5.8 amps when connected to a 120 V circuit?
18. What is the power of the frying pan in #17?
19. What current flows through a 100.0 W bulb connected to a 20.0 V electrical source?
20. An electrical appliance uses 6.0 kWh in a month. If the power company chargesc$0.08/kWh, what is the
cost to use this electrical appliance?
21. What is a series circuit?
.
22. What is a parallel circuit?
23. If one light goes out in a series circuit, do the remaining lights go out?
24. If one light goes out in a parallel circuit, do the remaining lights go out?
25. What happens to the equivalent (total) resistance in a series circuit when you add another resistor to it?
26. What happens to the equivalent resistance in a parallel circuit when you add another resistor to it?
27. What does an ammeter measure? How is it connected into a circuit?
28. What does a voltmeter measure? How is it connected into a circuit?
29. If there are three lamps connected in series, how many paths can the current take?
30. If there are three lamps connected in parallel, how many paths can the current take?
31. Determine the equivalent resistances for the following circuits:
32. Calculate the values represented in the missing blanks for the following circuit diagrams. Also, identify
whether the circuit is a series or parallelcircuit.
33. How is the magnetic field oriented around a magnet?
34. Where is the magnetic field the strongest?
35. What is the smallest magnet?
36. What happens to the magnetic field around a current-carrying wire if the current through it is reversed?
37. How does an electric motor work?
38. What are two ways to generate current in a wire?
39. How does an electric generator work?
40. What three factors does the strength of an electromagnet depend on?
41. What three factors does the voltage (and current) produced by a generator
depend on?
42. Why is the kinetic molecular theory important to thermodynamics?
43. Describe the three ways that heat can be transferred:
a. conduction :
b. convection :
a. radiation:
b.
44. How is temperature related to kinetic energy? What are the three temperature scales?