3. Increase load by 50 gm each time and measure time‘t’. Calculate period T for each case.

4 Plot the graph of T2 against M. Take (0, 0) origin. The graph is straight line. The intercept on negative M-axis gives mass of the spring (Ms)

Precautions: 1.The amplitude of oscillation should be as small as possible.. 2. The spring should oscillate in vertical plane only.

3. Take large number of oscillations & find the mean value. 4. There should not be twist in the string.

Results: Mass of the spring from the graph = Ms = ………… gm.

Experiment No. 3

Title: Sonometer - IAim: To verify First law of vibrating string & to determine unknown frequency of the tuning fork. Apparatus: Sonometer, slotted weights, set of tuning forks, paper rider, rubber pad.

Diagram:

String

Sonometer Box

First law of vibrating String: Fundamental frequency of string is inversely proportional to vibrating length, when tension & mass per unit length are constant.

Observation Table:Tension in the wire = T = ………… dynes

Experiment No. 1

Title: Simple PendulumAim: To find acceleration due to gravity by simple pendulum. Apparatus: Metal bob, thread, stand, Stop watch, Vernier Calipers, etc.

Diagram:

Observations:

1) Smallest division on main scale = S = …………………. cm.

2) No. of divisions on vernier scale = N = ………………..

3) Least Count ( L.C.) of vernier calipers = S / N = ………………..cm.

Observation Table: For radius of the bob.

Precautions:1. The length of the string should be as large as possible.2. The amplitude of the oscillation should be as small as possible.3. The pendulum should oscillate in one plane only.

Observation Table: For Period of simple pendulum

1

Obs.No.

Frequency n ( Hz)

Vibrating Length

L cm 1 / Lcm-1

nLMean

nL1 2 3

MeanL (cm)

1

2

3

4

5nx Lx= 1/Lx=

Obs.No.

M.S.R.a cm

VerniercoincidingDivisions

b div

Vernier ScaleReading

b x L.C.= c cm.

TotalReadinga + c cm

MeanDiameter

d cm

Radiusr = d/2 cm

1

2

3

Obs.No.

Lengthof

String

l cm

Length ofPendulum L =

( l + r) cm

Time for 20 Oscillations. Period

T =

sec

T2

sec2L / T2

cm/sec2

MeanL / T2

cm/sec2

1 2 3

Mean

tsec

1

2

3

4

5

6

Procedure: 1. Find least count of vernier calipers. 2. Measure diameter of the bob and calculate radius of the bob.3. Suspend the bob from the stand by light string.4. Take the length of the string as 50 cm.5. Measure the time for 20 oscillations. 6. Vary the length of the string from 70 to 120 cm.7. Find period of pendulum (T). Hence find L / T2 in each case.8. Calculate acceleration due to gravity.

Calculations: 1.The acceleration due to gravity ‘g’ = cm/sec2

2. Acceleration due to gravity ‘g’ = 4π2 x slope cm/sec2

Graph: L Slope

T2

Results: 1. Acceleration due to gravity ‘g’ by calculation = ………….cm/sec2

2. Acceleration due to gravity ‘g’ by graph = ………….. cm/sec2

Experiment No. 2Title: Spring – mass oscillator.Aim: To determine force constant & P.E. of a spring. Apparatus: Spring, Slotted weights, scale, retort stand, etc.

Diagram:

Observation Table:

Graph: Plot the graph of T2 against M. The intercept on negative M-axis gives mass of the spring (Ms) T2

(0,0) M Procedure:

1. Suspend the spring vertically from rigid support. Attach suitable mass (M) from the lower end of the spring.

2. Apply a small force to the mass attached in the downward direction so that there are vertical

oscillations of small amplitude of the spring. Measure the time for 20 oscillations twice. Observations:

1. Density of water = ρ = 1 gm/cm3

2. Angle of contact for water = θ = 0º3. Smallest division on main scale = S = …………………. cm. 4. No. of divisions on vernier scale = N = ………………..5. Least count of travelling microscope = S / N = ………………..cm.

2

Obs.No.

Mass attached to the spring

M gm

Time for 20 oscillations Period

sec

T2

sec2

1 2Meant sec

1

2

3

4

5

For Radius of the Capillary tube bore:

For height of water in capillary tube:

Calculations: But θ = 0º

Hence dyne / cm

Results: Surface tension of water = T = ……………… dyne / cm

Procedure:1). Measurement of height ‘h’: Take a clean capillary tube and fix it in the clamp vertically. Mount a thin needle parallel to the tube. Adjust the position of the cork so that the lower end of the needle just touches the water surface. Focus the microscope on water meniscus in capillary tube. Move the microscope vertically until the horizontal cross wire is tangential to the meniscus. Note the reading ‘a’ on the vertical scale. Focus the microscope on the tip of the needle. Note the microscope reading “b”. Take two more readings by dipping the capillary tube to different levels in water.2). Measurement of radius ‘r’: Clamp the capillary horizontally. Focus the microscope on the bore of the capillary. Adjust the cross wire tangential to the bore. Note the microscope reading ‘x’ cm. Move the microscope vertically by fine adjustment until the horizontal cross wire is tangential to the bore at the diametrically opposite point. Note the microscope reading ‘y’ cm. Graph:

n Slope = nL = ……..

nx

1 / Lx 1/L

Calculations: = …………. Hz

= …………..Hz

Results:1. Unknown frequency by calculation = nx = ………… Hz2. Unknown frequency by intercept from graph = nx = ………… Hz3. As the product nL is constant, first law of vibrating string is verified.4. As graph of n against 1/L is a straight line so first law of vibration string is

verified5. Unknown frequency from slope = nx = ………… Hz

Procedure:

Apply suitable weight to the sonometer wire. Both bridges are brought to the middle of the wire. Paper rider is kept on the wire midway between the bridges. The tuning fork of highest frequency is vibrated by striking it gently on the rubber pad & keep on the sonometer box. The bridges are moved such that the paper rider vibrates vigorously & thrown off the wire. The length between the bridges is measured as vibrating length. For the same tuning fork the experiment is repeated twice and mean resonating length is obtained. This procedure is repeated for other tuning forks of lower frequencies.

Precautions: 1. The tuning fork should be held by the stem only.2. The tuning fork should be vibrated gently.3. The paper rider should be placed at the centre of the wire between the

bridges.

Experiment No. 4

Title: Sonometer - II

Aim: To verify Second law of vibrating string & to determine unknown frequency of the tuning fork. Apparatus: Sonometer, slotted weights, set of tuning forks, paper rider, rubber pad.

Diagram: Same as in Experiment No. 3.

3

Obs.No.

Microscope Reading Diameterd = x– y cm

MeanDiameterd (cm)

Radius of borer = d/2 cm x (cm) y (cm)

1

2

Obs.No.

Microscope Reading Heighth = a – b

cm

Meanh (cm) a (cm) b (cm)

1

2

3

First law of vibrating String: Fundamental frequency of string is directly proportional to square root of tension when vibrating length & mass per unit length are constant.

Observation Table:Linear density of wire = m = ……………….. gm/cm

Graph: Slope =

L

Calculations : 1) = Hz

2) × Slope Hz

Results:

1. Frequency of tuning fork by calculation = n = ……………..Hz2. Frequency of tuning fork by graph = n = ……………..Hz

3. As is constant, Second law of vibrating string is verified.

4. As the graph of against L is a straight line, Second law of vibrating

string is verified.Procedure:

Apply suitable tension to the wire. Keep the bridges close together in the middle of the wire. Place a paper rider on the wire mid way between the bridges. The vibrated tuning

fork is held on the sonometer box with its stem in contact with the box. Adjust the distance between the bridges such that the paper rider vibrates vigorously and thrown off. Measure the distance between the bridges. This is vibrating length of the wire. Repeat twice & find mean vibrating length. Then increase the tension in steps of 500 gm wt. Repeat the procedure for other different tensions.

Precautions:

1. The paper rider should be placed at the centre of the wire between the bridges.

2. The vibrating tuning fork is held vertically such that its stem is in contact with the sonometer box.

3. Keep the wire under maximum tension. This will give maximum resonating length thereby minimizing the error in the measurement of L.

Experiment No. 5Title: Surface TensionAim: To determine surface tension of water by capillary rise method.Apparatus: Capillary tube, travelling microscope, clamp, retort stand, etc.

Diagram:

Experiment No. 8Title: Newton’s law of cooling.Aim: To Verify Newton’s law of cooling.Apparatus: Calorimeter, Constant temperature enclosure, thermometer, Retort stand, Stop clock, stirrer etc., Diagram:

4

Obs.No.

Mass attached to the wire M gm

TensionT = Mgdyne

Resonating Length L cm Mean

1 2Mean L

cm

1

2

3

4

Newton’s law of cooling: The rate of fall of temperature is directly proportional to the excess temperature of the body over the surroundings provided excess is small.

Observations: Room temperature = θ = ………… ºC

Obs.No

Timet min

Temp.θ ºC

Obs.No

Timet min

Temp.θ ºC

1 13

2 14

3 15

4 16

5 17

6 18

7 19

8 20

9 21

10 22

11 23

12 24

Precautions:1. While measuring rise of water in the capillary, water in the beaker should not be

touched with fingers as that action will change the S.T. of water.2. Capillary should be clean and wet inside.3. The microscope scale should be exactly vertical.4. The capillary should be dipped in water again & again so that there is no air bubble

inside it.

Experiment No. 6Title: Resonance tubeAim: To determine velocity of sound in air by resonance tube.Apparatus: Glass jar with water, metallic tube, rubber pad, meter scale, vernier calipers, set of tuning forks. Diagram:

L = + e

Observations:1. Least Count ( L.C.) of vernier calipers = ………………..cm2. Inner diameter of the tube = i) …………… ii) ………….. iii) …………...

Mean inner diameter = d = …………….. cm

End correction e = 0.3d = ………………cm For Resonating Length of air column:Graph:

n Slope = nL = …….. cm/sec

nx

1 / Lx 1/LCalculations: V = 4n L = 4 [Mean(nL)] = …………..cm/sec

= …………. Hz

By Graph: V = 4 (Slope) = …………..cm/sec

= …………..Hz

5

Obs.No.

Frequency n ( Hz)

Vibrating Length

cm

CorrectedLength

L = + e

cm

1 / Lcm-1

nL MeannL

1 2 3Mean

(cm)

1

2

3

4

5nx Lx= 1/Lx=

Results: 1. Velocity of sound in air = V = ………….cm/sec.2. Unknown frequency by calculation = nx = ………… Hz3. Velocity of sound in air by graph = V = ………….cm/sec.4. Unknown frequency by slope = nx = ………… Hz5. Unknown frequency by intercept from graph = nx = ………… Hz

Procedure: The least count of vernier calipers is determined. The inner diameter of the resonance tube is measured and mean diameter ‘d’ is obtained. The tuning fork of highest frequency is vibrated with rubber pad and held above the tube as shown in figure. The vibrating length of the tube is adjusted till loud sound is heard. The length of the tube above the water level is measured as ‘ ’. For the same tuning fork the readings are repeated and mean value is taken. The experiment is repeated for other tuning forks.Precautions:

1. The tuning fork is held above the tube with its plane of vibration vertical.2. The tuning fork should be vibrated gently.

Experiment No. 7Title: Melde’s ExperimentAim: To determine the frequency of alternating current (a.c.) by Melde’s expt.Apparatus: A.C. source, Electromagnet, vibrator, string, key, light pan & weights. Diagram:

Observations:1. Vibrating length of the string = L = ……………… cm.2. Mass of empty pan = M0 = ……………gm3. Mass per unit length of the string = m = ………………gm/cm.

Calculations: For parallel position.

Frequency of A.C.= n = Hz.

Results:

Frequency of A.C.= n = ……………………..Hz

Procedure: Keep the apparatus in parallel position. Pass the current. Add small mass in the pan. Adjust the position of vibrator so that well defined loops are obtained. Note the mass in the pan as M1 and number of loops as P. Reduce the number of loops in steps of one, by increasing the mass in the pan.

Precautions:1. The pan should be light.2. The length of the string between vibrator & pulley should be as large as

possible.3. The pan or string should not touch the table.4. The string between the vibrator & the pulley should be horizontal.5. The tension should be adjusted such that well defined loops are obtained

on the string.Observation Table:

ObsNo.

Unknown resistanceX Ω

R Ω

LX

cm LR

cm

X = Ω MeanΩ

1

2

X1

X1

X1 =

3

4

X2

X2

X2 =

5

6

XS

XS

XS =

7

8

XP

XP

XP =

Calculations: X =

6

Obs.No.

Mass in pan M1 gm

Total mass M =(M0+M1)

gm

TensionT=Mgdyne

No. of.Loops

Pρ

Meanρ

Length of loop=

1

2

3

4

5

XS = X1 + X2

XP =

Results:i) XS (Observed) = ……………….. Ωii) XS (Calculated) = ……………….. Ωiii) XP (Observed) = ……………….. Ωiv) XP (Calculated) = ……………….. Ω

Procedure: Make plug key K on. Connect one unknown resistance X1 in left gap. The jockey is touched to two ends of the bridge wire. The galvanometer should show opposite deflections. Take out some resistance from resistance box R. Touch the jockey at different points of the bridge wire and find the point of contact such that the galvanometer shows zero deflection. This is called null point. The value of R is so chosen that the null point should be in middle one-third part of the wire. The length of the wire opposite to X1 is taken as LX & the length of the wire opposite to R is taken as LR. The lengths LX & LR are measured up to null point. Again take reading by interchanging the positions of X1 & R. Repeat the procedure for X2. Then connect X1 & X2 in series & find LX & LR after interchanging the gaps. Also connect X1 & X2 in parallel in left gap & find LX & LR

after interchanging the gaps. Calculate XS & XP by formula. Hence verify laws of resistances in series & parallel by comparing observed & calculated values of XS

and XP

For rate of cooling:

Graphs:

θ θ 1

θ 2

(0,0) t (0,0) (θ - θ0)

Results: Th e graph of

against (θ -

θ0) is a straight line. Hence Newton’s law of cooling is verified.

Procedure: Note the room temperature. The calorimeter is filled to about its two third capacity with boiling water. The calorimeter is placed in constant temperature enclosure. The thermometer & stirrer are inserted in hot water. The stop clock is started & temp. of water is noted after every minute. The hot water is constantly stirred.A graph of temperature against time is plotted. It is a smooth exponentiall curve. Find the slopes at different temperatures & plot the second graph of (dθ / dt) against (θ - θ0). It is a straight line graph passing through the origin.Precautions:

1. The water in the calorimeter should be gently stirred.2. The initial temperature of water in the calorimeter should be 30 ºC above the

temperature of the surroundings.3. Time interval between two temperature readings should be 0.5 minute..4. Least count of thermometer should be small (0.5 ºC).

Experiment No. 9Title: Current sensitivity of Moving Coil Galvanometer ( M.C.G.)Aim: To find current sensitivity of moving coil galvanometer.Apparatus: Battery, reversing key, resistance box, galvanometer, plug key, microammeter etc. Circuit Diagram:

7

ObsNo.

Rate of cooling

Temperatures at whichSlopes are found

θ ºC

TemperatureExcess(θ - θ0) ºC

1

2

3

4

5

Observation Table:

ObsNo.

CurrentI Amp.

Gavanometer Deflection θ Sensitivity

div / amp

MeanSensitivityS div / A

BeforeReversing

AfterReversing

Mean θdiv.

1

2

3

4

5

6

Calculations: Sensitivity div / amp.

Graph:

θ Slope = S

IResults:

Sensitivity of galvanometer by calculation S = ………………div / amp.Sensitivity of galvanometer by graph S = ………………div / amp.

Procedure: The connections are made as given in the circuit diagram. High resistance key is removed from the resistance box. The plug key K is closed and the value of resistance R in R box is so adjusted that nearly full scale deflection in galvanometer is obtained. The defection in divisions and current in amperes is noted. Then the current is reversed by reversing key and the deflection is noted. The experiment is repeated for other values of resistance R.Precautions:

1. All connections should be tight.2. The keys of resistance box are not left loose.3. Initially one key of high resistance from the resistance box should be left

open to avoid the damage of electrical meters.4. All readings are also taken after reversing the reversing key.

Experiment No. 10Title: Meter Bridge (Laws of Resistances)Aim: To verify the laws of series and parallel combination of resistances.Apparatus: Meter Bridge, Two unknown resistances, slider, resistance box, Galvanometer, Battery, plug key, rheostat etc. Circuit Diagram:

+ -

Fig. (a) Fig. (b)

1. Law of Series: The equivalent resistance in series is equal to the sum of individual resistances.

2. Law of Parallel: The reciprocal of equivalent resistance in parallel arrangement is equal to the sum of reciprocals of individual resistances.

Sum & Difference method: Connect the two cells as shown in Fig. (a). The Cell E1 i.e Leclanche cell should be of greater E.M.F. Find the balancing length L1. Then connect the two cells as shown in Fig. (b). Find the balancing length L2.Precautions:

1. The battery must be of greater E.M.F. than the E.M.F. to be measured.2. While taking null point, the jockey should not be slide along the wire, but should be

touched at various points.3. In sum & difference method, E.M.F. of first cell in series should be of higher E.M.F.4. Positive of the battery & positive of the cell should be connected to common

terminal P of the wire.

Experiment No. 13Title: Potentiometer (Internal Resistance of Cell)Aim: To find internal resistance of a cell.

8

Apparatus: Potentiometer, galvanometer, Cell, Battery, keys, rheostat, resistance box, etc. Circuit Diagram:

+

_

Observation Table:

Obs.No.

Balancing length When K2 open L1 cm

Resistance fromResistance box

R Ω

Balancing length When K2 closed

L2 cm

InternalResistance Ω

Mean r

Ω

1

2

3

4

5

Calculations:

Precautions:1. A suitable value of R in resistance is adjusted such that null point is

obtained in the middle one-third of the bridge wire.2. Readings are taken after interchanging the gaps to minimize errors due to

non uniformity of wire.3. All connections must be tight.

Experiment No. 11Title: Meter Bridge (Kelvin’s Method)Aim: To determine the resistance of galvanometer by Kelvin’s method

using meter bridge. Apparatus: Meter Bridge, slider, resistance box, galvanometer, Battery, plug key, rheostat etc.

Circuit Diagram:

Observation Table:

Calculations: RG = Ω

Results: Resistance of Galvanometer = RG = ……………….. Ω

Procedure: Connections are made as shown in the circuit diagram.Plug key K is closed. Jockey is touched to two different points of the bridge wire, the galvanometer should show opposite deflection. The value of R is so chosen that there is no change in the deflection if the contact is made or broken. Such a point is the balance point. The balance point should be in the middle one-third of the bridge wire. LG & LR are measured. Experiment is repeated by interchanging the positions of galvanometer G and resistance box R.

Precautions:1. The balance point is obtained in the middle one-third of the bridge wire.

9

ObsNo. R

ΩLX

cmLR

cmRG = Ω Mean

RG Ω

1

2

3

Interchanging the positions of G and R

1

2

3

2. Readings are taken after interchanging the gaps.3. All connections must be tight.

Experiment No. 12Title: Potentiometer ( Comparison of E.M.Fs)Aim: To compare the e.m.fs of two cells using potentiometer by separate method and Sum & Difference method.Apparatus: Potentiometer, galvanometer, rheostat, jockey, Daniel Cell, Leclanche cell etc. Circuit Diagram:

+

_

Fig. (a) Fig. (b)

E1 = Leclanche Cell & E2 = Daniel Cell

Observation Tables:

i) For separate cell method:

Obs.No.

Balancing Length for

Mean

Cell E1

L1 cmCell E2

L2 cm

1

2

3

ii) For Sum & Difference method:

Obs. Balancing Length when Mean

No. Cell assist

L1 cmCell oppose

L2 cm

1

2

3

Calculations: 1. For individual method:

2. For Sum & Difference Method:

Results: 1. E1 / E2 (by separate method) = …………….

2. E1 / E2 (by sum & difference method) = …………….

Procedure:

Individual Method: First connect the cell E1 i.e. Leclanche cell in the circuit. Close the key. Touch the jockey to the points P & Q and see that the galvanometer deflections are opposite. If not, adjust the rheostat. Now touch the jockey at various points on the wire AB and find the null point where the galvanometer shows no deflection. Measure the length of the wire from the starting point A to null point. This is balancing length L1 for cell E1. Now disconnect the cell E1 & connect the Daniel cell E2. Find the balancing length L2 for the cell E2.

Graph:

Formula:

10

D.C. Resistance = R dc = Ω

A. C. Resistance =

Procedure: The connections are made as shown in the circuit diagram. The rheostat is used as a potential divider. Starting with lowest potential difference in the voltmeter, the P.D. is gradually increased & corresponding current I is measured with the help of milliammeter. Plot the graph current I (Amp) against potential difference V (Volt). Hence calculate d. c. & a. c. resistance of diode.

Results: 1. D.C. Resistance = ……………….. Ω

2. A. C. Resistance = …………………. Ω

Precautions:

1. p-n junction diode should be connected in forward biased mode only i.e. anode of the diode should be connected to positive of D.C. source & cathode of diode should be connected to negative of D.C. source.

2. Polarities of voltmeter and milliammeter should be maintained according to circuit diagram.

3. Rheostat of large value should be used.4. All the connections must be tight.5. Do not apply large D.C. voltage across the diode during forward bias.

Results: Internal resistance of the cell = r = ………….. Ω.

Procedure: Close the key K1. Adjust rheostat such that when jockey is touched to P & Q the galvanometer shows opposite deflection. With the key K2 open, touch the jockey at various points on the wire PQ & find the null point such that galvanometer shows no deflection. Measure the length of the wire from point P to null point. This is balancing length L1. Then by plucking out a resistance from the resistance box & by closing the key K2, balancing length L2 is obtained. The experiment is repeated for different values of R.

Precautions:

1. The positive of battery B & positive of cell E are connected to common terminal A.2. While taking null point, the jockey should not be slide along the wire but should be

touched at various points on the wire.3. The emf of the driving battery should be greater than the emf of the cell.4. All the connections should be tight.5. Keep all the keys in the resistance box tight.

Experiment No. 14Title: Tangent GalvanometerAim: To determine horizontal component of earth’s magnetic induction.Apparatus: Tangent galvanometer, cell, plug key, Reversing key, spirit level, Rheostat, milliammeter etc. Circuit Diagram:

Observations:

1. Number of turns in the coil = n = ……………

2. Circumference of the coil = C = ………………m

3. Radius of the coil r = C / 2π = ………………….m.

Observation Table:

ObsNo.

CurrentI amp

Deflections in TangentGalvanometer

MeanDeflection θ degree tan θ

ReductionFactor Mean

Kθ1 θ2 θ3 θ4

11

Calculations: BH = x mean (K) ……. Wb / m2

Where = 4 π x 10-7 Wb / A-m

Graph: Slope =

I

tan θ

Calculations: BH = (Slope) …………………………. Wb / m2

Results: 1. BH (By Calculation) = ……………………… Wb / m2

2. BH (By Graph) = ……………………… Wb / m2

Procedure: 1. Level the Tangent galvanometer with help of sprit level & leveling screws.2. Adjust T.G. in magnetic meridian i.e. the plane of the coil should be parallel

to the length of the needle.3. Adjust magnetometer box such that the pointer is on 0-0 marks of the

scale. Close the key K. By adjusting rheostat, pass a suitable current through the circuit so that the deflection of the needle is about 30º. Note milliammeter reading I & the readings at both ends of the pointer of the galvanometer. Reverse the reversing key. Again note the readings at both ends of the pointer. Change the current by rheostat & repeat the procedure for different values of current. The deflections should be between 30º to 60º.

Precautions: 1. The deflections of galvanometer should be within 30º to 60º.2. Readings of pointer in T.G. should be taken by removing the parallax between

pointer & its image.3. Readings are taken by reversing the current in T.G. coil.4. All connections must be tight.5. The magnetic fields of ammeter & rheostat will affect the needle of T.G. Hence

keep them at a sufficiently large distance from T.G.

Experiment No. 15Title: P-N junction diode characteristics.

Aim: To study characteristics of P-N junction diode when it is forward biased.Apparatus: P-N junction diode, D.C. battery, plug key, Voltmeter, milliammeter,

Rheostat, etc. Circuit Diagram:

Observation Table:

Experiment

No. 18Title: Basic Logic gates.Aim: To verify the truth tables of logic gates.

Apparatus: IC-7404, 7408, 7432, 7400, 7402 LEDs, DPDT Toggle switches etc.

12

Obs.No.

Potential DifferenceV volts

Current I A

1 0.1

2 0.2

3 0.3

4 0.4

5 0.5

6 0.6

7 0.7

8 0.8

9 0.9

10 1

Circuit diagrams Pin Connections of IC

1. AND Gate:

+ve

2. NOT Gate:

+ve

3. OR Gate:

+ve

Experiment No. 16Title: Zener diode characteristics.Aim: To study characteristics of zener diode when it is reverse biased.Apparatus: Zener diode, 9 V D.C. source, Voltmeter, milliammeter, Rheostat, etc.

Circuit Diagram:

Observation Table:

Characteristics of Zener Diode:

Results: Break down voltage = VB = ………… Volt

13

Obs.No.

Potential DifferenceV volts

Current I A

1 0.5

2 1

3 1.5

4 2

5 2.5

6 3

7 3.5

8 4

9 4.5

10 5

Procedure:

Connect 9 V D.C. source to rheostat. To measure current milliammeter is connected in series with zener diode. Zener diode is connected in reverse bias condition. Voltmeter is connected across the zener diode. Measure zener current & voltage by varying the rheostat. Plot the characteristics of zener diode i.e. current against voltage in reverse biased condition.

Precautions:

1. The zener diode should be connected in reverse biased mode.2. Polarities of meters should be properly maintained.3. All connections must be tight.4. Rheostat should be used as potential divider.

Experiment No. 17Title: Full wave Rectifier.

Aim: To study Load regulation of full wave rectifier.Apparatus: Transformer 6 - 0 - 6 V,500 mA, Diodes BY 127, Condenser 2200 μf, 12V, Potentiometer,Voltmeter, milliammeter, etc. Circuit Diagram:

Observation Table:

Procedure: Connect the circuit as shown in the circuit diagram. Connect AC voltage to primary of the transformer. Anodes of diodes D1 & D2 are connected to S1 & S2

terminals of the secondary of the transformer. The common cathodes of two diodes is connected to + ve of the condenser. The negative of the condenser is connected to centre tap of the transformer. DC output voltage appears across the condenser. Plot the graph of VL (volt) against IL (Amp).

Load Regulation: Connect potentiometer ( 10 KΩ ) across the output voltage. Vary the load & measure the output voltage. Measure output voltage Vr.m.s. by AC meter & DC voltage Vdc by DC meter.

Calculation: Ripple Factor =

Results: Ripple factor for given current = …………………

Precautions:1. Always start from

maximum load.2. Connect the diodes &

meters with proper polarity.

3. Positive of the condenser must be connected to positive

of D.C. supply.4. Connect the primary to

A.C. mains & secondary to diodes.

14

Obs.No.

Load CurrentIL Amp

Output VoltageVL volts

1

2

3

4

5

6

7

8

5. All connections must be tight.

4. NAND Gate:

5. NOR Gate:

Observation Tables: Truth Tables for Logic gates: Truth Tables Boolean Equation 1. AND Gate IC-7408

Boolean equaitY = A · B

2. OR Gate IC-7432

Boolean EquatiY = A + B

3. NOT Gate IC-7404

Boolean equationY = Ā

15

A B Y 0 0 00 1 0

1 0 01 1 1

A B Y0 0 00 1 11 0 11 1 1

A Y0 11 0

Truth Tables Boolean Algebra

4. NAND Gate IC-7400

Boolean AlgeY =

5. NOR Gate IC-7402

Boolean AlgeY =

Procedure:

Take any one of the IC consider one of its gate. Connect the input terminals of gate to the switches poles and two terminals of switch to +5V & -5V. Connect LED to the output of gate through resistor. Connect +5V to pin 14 of IC & -5V to pin 7 of the IC. Now give different combinations of inputs & note the output states & verify the truth table for the gate. Glowing LED indicates logic 1 & LED in off position indicates logic 0 state.

Results: The truth tables of all the logic gates are verified.

Precautions:

1. The supply voltage should be exactly 5V d.c.2. For IC, socket should be used.3. Place the IC in the socket properly.4. Do not short the output of logic gates. It may damage the logic circuit.

Scheme of Marking

16

A B Y0 0 10 1 11 0 11 1 0

A B Y0 0 10 1 01 0 01 1 0

Sr.No. Title head for marks Marks

1 Diagram 1

2 Setting or Connections 1

3 Formula or Law 1

4 Observations 3

5 Graph / Calculations or both 1

6 Results or Conclusions with units 1

7 Precautions 1

8 Journal 2

NATURAL TANGENTS

17

18

Name:…………………………………………………

Roll No. ………………………………….

Batch:……………………………………

19

XIIth Science

Physics Practical

Handbook

By

Experienced Teachers

For Private Circulation only.

Name: ………………………………………………………………

Roll No: ……………………

Batch: ……………

CONTENTS

NATURAL TANGENTS

20

Experiment No.

Title of the Experiment PageNo.

1 Simple Pendulum 1

2 Spring-mass Oscillator 3

3 Sonometer - I 4

4 Sonometer - II 6

5 Surface Tension 7

6 Resonance Tube 9

7 Melde’s Experiment 10

8 Newton’s Law of Cooling 12

9Current sensitivity of Moving Coil

galvanometer

14

10 Meter Bridge ( Laws of Resistances) 15

11 Meter Bridge ( Kelvin’s Method) 17

12 Potentiometer ( Comparison of E.M.Fs.) 18

13 Potentiometer (Internal Resistance of a Cell.) 20

14 Tangent Galvanometer 21

15 p – n Junction diode Characteristics 23

16 Zener diode Characteristics 25

17 Full Wave Rectifier 26

18 Basic Logic gates. 28

Log Tables 32