Kerala Board Solutions for Chapter: Motion, Exercise 8: Let us assess

What is the acceleration of a car which started from rest and acquired a velocity of $40 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$ in $8 \mathrm{s}$?

A car covered the first $400 \mathrm{m}$ distance with a speed of $8 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$, the next $1200 \mathrm{m}$ with a speed $12 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$ and the last $360 \mathrm{m}$ with a speed of $12 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$. Calculate the average speed of the car.

Does a body have acceleration in the following situation? Why?

A body travelling along a straight line with uniform velocity.

Does a body have acceleration in the following situation? Why?

A body travelling along a straight line with non-uniform velocity.

Does a body have acceleration in the following situation? Why?

A body travelling along a circular path with uniform speed.

Does a body have acceleration in the following situation? Why?

A body travelling along a circular path with non-uniform speed.

A lorry travelling with a velocity of $30 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$ came to rest in $5 \mathrm{s}$. What is its acceleration?

What is the displacement of a car in $30 \mathrm{s}$ if it is travelling with a velocity of $15 \raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{s}$}\right.$?