# Relative Velocity MCQ Science

50 Questions 30 Mins

The speed of one body with respect to the speed of another is called the relative speed of the first body to the second. Whereas the relative speed is measured in the frame in which an object is at rest or moving with respect to an absolute frame.

In this case, the resulting speed would be 75 km/hr; that is the speed of the aircraft with respect to an observer on the ground. Suppose that an aircraft travelling at a speed of 100 km/hr with respect to the air encounters a headwind at 25 km/hr.

However, if the two are travelling in opposite directions, then the relative speed of the one machine to the other is thus 60 ms-1 (see figure 1). We present the relative movement first in a single dimension, as two velocity vectors are simplified by having only two possible directions.

If we chose the positive direction east and the reference frame of the Earth, we can write the velocity of a train with respect to Earth as (vecv_TE)=10m/s(hati)east, with the subscripts TE denoting the train and Earth. If we choose east as the positive direction and Earth as the reference frame, then we can write the velocity of the train with respect to the Earth as (vec v _ TE ) = 10 m/s (hat i ) east, where the subscripts TE refer to train and Earth. In special relativity, V-B|AdisplaystylevecV_mathrmB|A is the speed at which an object or observer b is at the still frame relative to the other object or observer a.

Following are some of the multiple choice questions on the Relative Velocity with answers that will help the students in developing their knowledge.

## Relative Velocity MCQ

• 8 s
• 10 s
• 15 s
• 30 s

• 0 m/s
• 8 m/s
• 9 m/s
• 10 m/s

• 0 m/s
• 6 m/s
• 12 m/s
• 24 m/s

• 0 m/s
• 4 m/s
• 8 m/s
• 16 m/s

### 5. Observers using different ___________________ may measure different velocities for an object in motion

• frame of reference
• relatives of motion
• projectile motions
• constant velocity

• 248 m/s
• 249 m/s
• 251 m/s
• 253 m/s

• 5 km/hr
• 11.18 km/hr
• 15 km/hr
• 30 km/hr

• 0 m/s
• 20 m/s
• 15 m/s
• 30 m/s

• 0 m/s
• 6 m/s
• 12 m/s
• 24 m/s

### 10. What method is used to find relative value for any vector quantity?

• Vector sum
• Vector difference
• Vector multiplication
• Vector division

### 11. What does relative motion signify?

• The motion of a body with respect to other body
• Uniformly accelerated
• Non-uniformly accelerated
• Motion along a curve

### 12. A body A is moving in North direction, while another body B is moving towards South. Velocity of A is greater than that of B. If North is taken as positive, which of the following relative velocities is positive?

• Velocity of A with respect to B
• Velocity of B with respect to A
• Velocity of A with respect to ground
• Velocity of B with respect to ground

### 13. An observer is sitting on a car moving with some constant velocity. The observer sees things around him, in the

• Relative frame of reference
• Absolute frame of reference
• Valid frame of reference
• Ground frame of reference

• -3 m from A
• 3 m from A
• 4 m from A
• 5 m from A

• 20 m/s
• 25 m/s
• -30 m/s
• 30 m/s

### 16. If two bodies are moving in opposite directions with non-zero velocities, which of the following statements is true?

• Relative velocity > Absolute velocity
• Relative velocity < Absolute velocity
• Relative velocity = Absolute velocity
• Relative velocity

• 0m/s
• -5m/s
• 10m/s
• 15m/s

### 18. What is the correct formula for relative velocity of a body A with respect to B?

• Vector VR = Vector VB – Vector VA
• Vector VR = Vector VA x Vector VB
• Vector VR = Vector VA + Vector VB
• Vector VR = Vector VA – Vector VB

• Absolute
• Relative
• Circular
• Parabolic

• 15 km/hr
• 60 km/hr
• 80 km/hr
• 145 km/hr