A body can have zero average velocity but not zero average speed. Justify giving an example.
Explain the following type of motion with one example of each
$(i)$ Acceleration is positive
$(ii)$ Acceleration is negative
$(iii)$ Acceleration is zero.
Distinguish between terms speed and velocity.
Answer the following questions
$(i)$ State the type of motion shown by a freely falling stone.
$(ii)$ When a stone is thrown vertically upwards its velocity is continuously decreased. Why ?
$(iii)$ Give an example of a motion in which average velocity is zero, but the average speed is not zero.
Write true or false for the following statements
A body is said to be at rest, if it does not change its position with respect to the reference point.