Embibe Experts Solutions for Chapter: Rectilinear Motion, Exercise 2: Exercise 2

A parachutist with total weight $75 \mathrm{kg}$ drops vertically onto a sandy ground with a speed of $2 \mathrm{m} {\mathrm{s}}^{-1}$ and comes to a halt over a distance of $0.25 \mathrm{m}$. The average force from the ground on her is close to-

A person walks $25°$ north of east for $3.18 \mathrm{km}$. How far would she have to walk due north and then due east to arrive at the same location?

(Take, $\cos 25°=0.906$)

A stone thrown down with a speed $u$ takes a time $t_1$, to reach the ground, while another stone, thrown upwards from the same point with the same speed, takes time $t_2$. The maximum height the second stone reaches from the ground is

A student performs an experiment to determine the acceleration due to gravity $g$. The student throws a steel ball up with initial velocity $u$ and measures the height $h$ travelled by it at different times $t$. The graph the student should plot on the graph paper to readily obtain the value of $g$ is-

A person goes from point $P$ to point $Q$ covering $\frac{1}{3}$ of the distance with speed $10 \mathrm{km} {\mathrm{h}}^{-1}$, the next $\frac{1}{3}$ of the distance at $20 \mathrm{km} {\mathrm{h}}^{-1}$ and the last $\frac{1}{3}$ of the distance at $60 \mathrm{km} {\mathrm{h}}^{-1}$. The average speed of the person is

A ball is dropped vertically from height $h$ and is bouncing elastically on the floor (see figure). Which of the following plots best depicts the acceleration of the ball as a function of time.

A particle starts moving along a line from zero initial velocity and comes to rest after moving distance $d$. During its motion it had a constant acceleration $f$ over $\frac{2}{3}$ of the distance, and covered the rest of the distance with constant retardation. The time taken to cover the distance is

If a ball is thrown at a velocity of $45 \mathrm{m} {\mathrm{s}}^{-1}$ in vertical upward direction, then what would be the velocity profile as a function of height? Assume $g=10 \mathrm{m} {\mathrm{s}}^{-2}$.