Which of the following statement is a false statement?
Which of the following statement is a false statement?
The correct option is B A body can have a constant velocity and still have varying speeds.
Step 1: Definition of the used terms
Speed :
It is defined as the ratio of distance traveled by the object per time taken to complete that distance.
It is a scalar quantity; so, it only depends on the magnitude, and does not depends on the direction of motion.
Velocity:
It is defined as the ratio of displacement of the object to the total time taken,
It is a vector quantity; so, it depends on both the magnitude and direction of the motion.
Acceleration :
Acceleration is defined as the change in velocity per unit of time.
It is a scalar quantity.
Step 2: Observations
a)
- A body can have zero velocity and still be accelerated.
- For example, consider a ball that is thrown vertically upward.
- After reaching the maximum height, that ball comes to rest for an instant of time.
- At that maximum height, the velocity of the ball is zero, but that ball will have acceleration due to gravity.
- So, the statement given in option (a) is true.
b) A body can not have a constant velocity with varying speeds.
- In order to have a constant velocity, speed needs to be constant. because velocity depends on the direction.
- So, the statement which is given in option (b) is false.
c) It is possible to have constant speed with changing velocity,
- Speed is a scalar quantity.
- For example, Consider an athlete who is running on a circular track with constant speed.
- Here the velocity of the athlete is non-uniform because the direction of the object is changing every time.
- So, the statement in (c ) is true.
d) The direction of the velocity of the body can change when its acceleration is constant.
- For example; Consider a ball that is thrown horizontally up to some distance.
- Here, the direction of velocity continuously changes.
- But acceleration due to gravity acting on the ball is constant.
- So, the statement in (d) is true.
Hence,
The statement given in (b) is a false statement.
A body can have a constant velocity and still have varying speeds.
Step 1: Definition of the used terms
Speed :
It is defined as the ratio of distance traveled by the object per time taken to complete that distance.
It is a scalar quantity; so, it only depends on the magnitude, and does not depends on the direction of motion.
Velocity:
It is defined as the ratio of displacement of the object to the total time taken,
It is a vector quantity; so, it depends on both the magnitude and direction of the motion.
Acceleration :
Acceleration is defined as the change in velocity per unit of time.
It is a scalar quantity.
Step 2: Observations
a)
- A body can have zero velocity and still be accelerated.
- For example, consider a ball that is thrown vertically upward.
- After reaching the maximum height, that ball comes to rest for an instant of time.
- At that maximum height, the velocity of the ball is zero, but that ball will have acceleration due to gravity.
- So, the statement given in option (a) is true.
b) A body can not have a constant velocity with varying speeds.
- In order to have a constant velocity, speed needs to be constant. because velocity depends on the direction.
- So, the statement which is given in option (b) is false.
c) It is possible to have constant speed with changing velocity,
- Speed is a scalar quantity.
- For example, Consider an athlete who is running on a circular track with constant speed.
- Here the velocity of the athlete is non-uniform because the direction of the object is changing every time.
- So, the statement in (c ) is true.
d) The direction of the velocity of the body can change when its acceleration is constant.
- For example; Consider a ball that is thrown horizontally up to some distance.
- Here, the direction of velocity continuously changes.
- But acceleration due to gravity acting on the ball is constant.
- So, the statement in (d) is true.
Hence,
The statement given in (b) is a false statement.
