Rate of Change of Velocity

A cyclist rolls down a hill. He starts from rest and after $8 \mathrm{s}$ he is travelling at $13.6 \mathrm{m}/\mathrm{s}$. Then his acceleration will be $\mathrm{K} \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{${\mathrm{s}}^2$}\right.$. Find the value of $\mathrm{K}$.

Newton's First Law of Motion states that if there is no force is acting on a body then its velocity does not change and the body will not accelerate.

Name the quantity which is defined as the rate of change of velocity.

What name is given to the negative acceleration?

(Choose from the following: retardation/ centripetal acceleration)

A ball hits a wall horizontally at $6.0 \mathrm{m} {\mathrm{s}}^{-1}$. It rebounds horizontally at $4.4 \mathrm{m} {\mathrm{s}}^{-1}$. The ball is in contact with the wall for $0.040 \mathrm{s}$. What is the acceleration of the ball?

In daily life, you come across a range of motion in which acceleration is non-uniform. Identify one example.

In daily life, you come across a range of motion in which acceleration is uniform. Identify one example.

In daily life, you come across a range of motion in which acceleration is against the direction of motion. Identify one example.

In daily life, you come across a range of motion in which acceleration is in the direction of motion. Identify one example.

Define acceleration. State its SI unit. When is the acceleration zero? Give one example when the body at rest possesses non zero acceleration.

When do we say that acceleration of a body is non-uniform? Give one example.

When do we say that acceleration of a body is uniform?

Give one example of a situation in which acceleration of a body is negative.

Give one example of a situation in which velocity of a body is in opposite direction to its acceleration.

An object is dropped from rest at a height of $150 \mathrm{m}$ and simultaneously another object is dropped from rest at a height of $100 \mathrm{m}$. What is the difference in their heights after $2 \mathrm{s}$ if both the objects drop with same acceleration? How does the difference in heights vary with time?

Define acceleration. When is the acceleration of a body positive and negative.

Draw velocity time graph for an object having uniformly accelerated motion.

Distinguish between uniform and non-uniform acceleration.

A train starts from rest and accelerates uniformly for $5 \mathrm{minutes}$. If it attains a velocity of $90 \mathrm{km} {\mathrm{h}}^{-1}$, find its acceleration.

Why does a freely falling body demonstrate accelerated motion?