Relative Velocity MCQ

The relative velocity of one item in relation to another is the rate at which one thing moves in relation to another. We may therefore grasp the temporal rate of change of relative location of one item with respect to another using relative velocity. In order to calculate relative velocity, we must first determine whether two objects or bodies are travelling in the same direction. A boat crossing a swiftly moving river or a jet flying through the air facing wind. In all of these circumstances, we must consider the medium’s impact on the item in order to fully explain the object’s motion. While doing so, we calculate the item’s relative velocity, taking into consideration both the particle’s and the medium’s velocity. As a result, a body’s relative velocity is defined as its velocity relative to another observer. It is the rate at which the relative position of one body in relation to another item changes over time.

1. When a body moves in relation to a stationary frame, its motion is referred to as
2. a) Absolute
3. b) Relative
4. c) Circular
5. d) Parabolic

Answer: a

Explanation: Absolute motion is motion in relation to a stationary frame. The term “relative motion” refers to movement in relation to a moving frame of reference.

2. A tiny brick is put on top of another block that is travelling at 5m/s. What is the little block’s absolute velocity?
3. a) 5m/s
4. b) 10m/s
5. c) 0m/s
6. d) 14m/s

Answer: a

Explanation: The little block’s absolute velocity is the same as the block travelling at 5m/s. Because absolute velocity is measured in terms of the ground frame, this is the case. The little block’s relative velocity with regard to the other block is zero.

3. What is the accurate formula for calculating the relative velocity of a body A in relation to a body B?
4. a) Vector VR = Vector VA – Vector VB
5. b) Vector VR = Vector VA + Vector VB
6. c) Vector VR = Vector VA x Vector VB
7. d) Vector VR = Vector VB – Vector VA

Answer: a

Explanation: The relative velocity of one body to another may be calculated by subtracting their respective velocities in the sequence in which they occur. This rule applies to all vector values, not only velocity.

4. A body A has a relative velocity of 5 m/s with regard to a body B. Body B has an absolute velocity of 10 m/s. Both bodies are travelling in the same direction at the same time. What is body A’s absolute velocity?
5. a) 10m/s
6. b) 15m/s
7. c) -5m/s
8. d) 0m/s

Answer: b

Explanation: We’ll apply the relative velocity formula, Vector VR = Vector VA – Vector VB, in this case. The velocity vectors are of the same sign because both bodies are travelling in the same direction. VA = 15m/s since VR = 5 and VB = 10.

5. Which of the following assertions is true if two bodies are travelling in opposing directions with non-zero velocities?
6. a) Relative velocity > Absolute velocity
7. b) Relative velocity < Absolute velocity
8. c) Relative velocity = Absolute velocity
9. d) Relative velocity <= Absolute velocity

Answer: a

Explanation: Vector VR = Vector VA – Vector VB is the formula for relative velocity. When both velocities are in the same direction, the equation is VR = VA – (-VB). As a result, the magnitudes add up, and the relative velocity of either of the two bodies is larger than its absolute velocity.

6. An automobile is travelling at 20 miles per hour, while another is travelling at 50 miles per hour. What is the first car’s relative velocity in relation to the second?
7. a) 30 m/s
8. b) -30 m/s
9. c) 20 m/s
10. d) 25 m/s

Answer: b

Explanation: Relative velocity is calculated using the formula VR = Vector VA – Vector VB. The relative velocity = 20-50 = -30 m/s if the automobiles are moving in the same direction. The second car’s relative velocity to the first is 30 metres per second.

7. A vehicle is travelling at 40 miles per hour, while a train is travelling at 80 miles per hour. In relation to the vehicle, how quickly is the rain moving?
8. a) 40 m/s faster
9. b) -40 m/s faster
10. c) 40 m/s slower
11. d) 60 m/s slower

Answer: a

Explanation: We need to determine the train’s relative velocity to the truck, which is VR = VA-VB, VB = 40, VA = 80. When we solve the problem, we obtain VR = 40 m/s. As a result, the train will accelerate by 40 metres per second.

8. A point A is positioned 7 metres from the origin, and a point B is positioned 10 metres from the origin. What is B’s relative location in relation to A?
9. a) 3 m from A
10. b) 4 m from A
11. c) -3 m from A
12. d) 5 m from A

Answer: a

Explanation: B’s relative displacement with regard to A is equal to B’s displacement minus A’s displacement. When we solve the problem, we obtain relative displacement = 3 m. As a result, B is located 3 metres away from A.

9. An observer is seated in a vehicle that is driving at a steady speed. In the ____, the observer observes objects around him.
10. a) Relative frame of reference
11. b) Absolute frame of reference
12. c) Valid frame of reference
13. d) Ground frame of reference

Answer: a

Explanation: The observer is not stationary in relation to the ground. The observer is immobile in relation to the moving car’s frame of reference, or relative frame of reference. Everything surrounding the observer will be seen via the lens of the relative frame of reference.

10. A body A is travelling to the north, while another body B is moving to the south. The velocity of A exceeds that of B. Which of the following relative velocities is positive if North is treated as positive?
11. a) Velocity of A with respect to B
12. b) Velocity of B with respect to A
13. c) Velocity of A with respect to ground
14. d) Velocity of B with respect to ground

Answer: a

Explanation: Vector VR = Vector VA – Vector VB is the formula for relative velocity. Because A’s velocity is larger in magnitude, A’s relative velocity will be positive. The relative velocity will be in a northerly direction.

11. A body A is travelling to the north, while another body B is moving to the south. The velocity of A exceeds that of B. Which of the following relative velocities is positive if North is treated as positive?
12. a) Velocity of A with respect to B
    b) Velocity of B with respect to A
    c) Velocity of A with respect to ground
    d) Velocity of B with respect to ground
    View Answer

Answer: a

Explanation: Vector VR = Vector VA – Vector VB is the formula for relative velocity. Because A’s velocity is larger in magnitude, A’s relative velocity will be positive. The relative velocity will be in a northerly direction.