Lakhmir Singh and Manjit Kaur Solutions for Chapter: Motion, Exercise 3: Long Answer Type Questions

What is meant by the term 'acceleration'? State the $\mathrm{SI}$ unit of acceleration.

Define the term 'uniform acceleration'. Give one example of a uniformly accelerated motion.

The distance between Delhi and Agra is $200 \mathrm{km}$. A train travels the first $100 \mathrm{km}$ with a speed of $50 \mathrm{km} {\mathrm{h}}^{-1}$. How fast must the train travel the next $100 \mathrm{km}$ , so as to average $70 \mathrm{km} {\mathrm{h}}^{-1}$ for the whole journey?

A train travels the first $15 \mathrm{km}$ at a uniform speed of $30 \mathrm{km} {\mathrm{h}}^{-1}$; the next $75 \mathrm{km}$ at a uniform speed of $50 \mathrm{km} {\mathrm{h}}^{-1}$; and the last $10 \mathrm{km}$ at a uniform speed of $20 \mathrm{km} {\mathrm{h}}^{-1}$. Calculate the average speed for the entire train journey?

A car is moving along a straight road at a steady speed. It travels $150 \mathrm{m}$ in $5 \mathrm{s}$. What is its average speed?

A car is moving along a straight road at a steady speed. It travels $150 \mathrm{m}$ in $5 \mathrm{s}$. How far does it travel in one second?

A car is moving along a straight road at a steady speed. It travels $150 \mathrm{m}$ in $5 \mathrm{s}$. How far does it travel in $6$ seconds?

A car is moving along a straight road at a steady speed. It travels $150 \mathrm{m}$ in $5 \mathrm{s}$. How long does it take to travel $240 \mathrm{m}$?