Motion in a Straight Line MCQs
1. A body covers 16, 18, 20, 22 meters in 5th, 6th, 7th and 8th seconds respectively. Which of the following statements is true about the body?
a) The body moves with a uniform velocity from rest
b) The body from rest moves with uniform acceleration
c) The body moves with an initial velocity and moves with uniform acceleration
d) The body moves with an initial velocity and then moves with uniform velocity
Answer: (c) The body moves with an initial velocity and moves with uniform acceleration
2. What can be said about the displacement of the body if it covers a distance of zero?
a) It is zero
b) It cannot be zero
c) It may or may not be zero
d) It is negative
Answer: (a) It is zero
3. An athlete finishes a round of circular track of radius R in 40 sec. What is his displacement at the end of 2 min 20 sec?
a) 2R
b) 2πR
c) 7πR
d) Zero
Answer: (d)2R
4. A man leaves home for a cycle ride and comes back home after an half-an-hour ride covering a distance of one km. What is the average velocity of the ride?
a) 10 kms-1
b) ½ kms-1
c) 2 kms-1
d) Zero
Answer: (d) Zero
5. A bird flies with a speed of 10 km/hr and a car moves with uniform speed 8 km/hr. Both start from B to A at the same instant (BA = 40 km). The bird after reaching A flies back immediately to meet the approaching car. Once it reaches the car, it flies back to A. The bird repeats this until both the car and the bird reach A simultaneously. What is the total distance flown by the bird?
a) 80 km
b) 50 km
c) 40 km
d) 30 km
Answer: (b) 50 km
6. Elephants A, B and C move with a constant speed in the same direction along a straight line as shown in the figure. The speed of the elephant A is 5 m/s and the speed of the elephant C is 10 m/s. Initially, the separation between A and B is d and between B and C is also d. When B catches C, the separation between A and C becomes 3d. What will the speed of B be?
a) 5 m/s
b) 7.5 m/s
c) 15 m/s
d) 20 m/s
Answer: (c) 15 m/s
7. Which of the following remains constant if a body travels with constant acceleration?
a) Time
b) Velocity
c) Displacement
d) None of the above
Answer: (d) None of the above
