5-ITEM MCQS IN KINEMATICS

1) What do you call the total length traveled by an object in a given time?

a. Distance

b. Displacementc. Speed

d. Acceleration

2) The slowing down of an object’s motion is more appropriately called _______.

a. Decelerationb. Displacement

c. Speed

d. Velocity

3) A bus moves along PIE at a constant speed of 60 kph in 2 hours. What is its acceleration?

a. 0 ms-2

b. 10 ms-2

c. 60 ms-2

d. 120 ms-2

4) A car moves at a uniform speed of 20 ms-1 in 1.5 minutes. How far did it go during that period?

a. 0.6 km

b. 1.8 km

c. 3.0 km

d. 4.1 km

5) A train comes to a stop in 45 seconds from a speed of 400 m/s. Calculate its deceleration.

a. About 9 ms-

2

b. About 12 ms-2

c. About 15 ms-2 d. About 19.6 ms-2

Correct!Congratulations.

View explanation #1.

Correct!Congratulations.

View explanation # 2.

Correct!Congratulations.

View explanation # 3.

Correct!Congratulations.

View explanation # 4.

Correct!Congratulations.

View explanation # 5.

Wrong!You may try again.

Explanation # 1:

Total length is the total distance d traveled by an object. Given time is the time elapsed t to travel a certain distance. If you divide distance by time, you get speed v. In symbols,

v = d/t

Explanation # 2:

In the physical world, the slowing down or coming to a stop of an object is called negative acceleration or, more appropriately, deceleration. It happens when the final velocity of an object is less than its initial velocity.

Explanation # 3:

An object that moves with a constant speed has zero acceleration. You can prove this mathematically by using the equation:

You can clearly infer from the equation that if vi and vf are the same, the acceleration becomes zero, no matter how long the object travels.

a = (vf-vi)/t

Explanation # 4:

Time must be expressed in seconds. By converting, 1.5 minutes is equal 90 seconds. Since v = d/t , and substituting the values:

v = d/t 20 ms-1 = d / (90s)

d = (20 ms-1) (90s) d = 1800 m = 1.8 km

Explanation # 5:

In the physical world, deceleration means slowing down of an object’s motion. In the problem, vi = 400m/s, vf = 0, and t = 45 s. Since a = (vf-vi)/t , and substituting the values:

a = (vf-vi)/t

a = (0 m/s – 400 m/s) / 45 s

a = 8.88 m/s2

THANK YOU!

This is the end of this test.

Prepared by:

RONALD P. DIANARamon Magsaysay (Cubao) HS – Philippines

Under the supervision of:

Prof. PHILIP WONGNat’l. Inst. Of Education (NIE) – Singapore