Embibe Experts Solutions for Chapter: Kinematics, Exercise 4: Exercise-4

A projectile is thrown with a speed $v$ at an angle $\mathrm{\theta }$ with the vertical. Its average velocity between the instants it crosses half the maximum height is

If $4 \mathrm{seconds}$ be the time in which a projectile reaches a point $P$ of its path and $5 \mathrm{seconds}$ the time from $P$ till it reaches the horizontal plane through the point of projection. The height of $P$ above the horizontal plane will be $-\left[g=9.8 \mathrm{m} {\mathrm{s}}^{-2}\right]$

Two objects moving along the same straight line are leaving point $A$ with an acceleration $a, 2a \&$ velocity $2u, u$, respectively at time $t=0.$ The distance moved by the object with respect to point $A$ when one object overtakes the other is

A particle is moving along $x-$axis with constant acceleration. At $t=0$ the particle is at $x=3 \mathrm{m}$ and $\frac{dx}{dt}=+4 {\mathrm{ms}}^{-1}$. The maximum value of $x$ co-ordinate of the particle is observed $2 \mathrm{s}$ later. Starting from $t=0 \sec$, after what time particle reaches its initial position again?

The displacement $x$ and time of travel $t$ for a particle moving on a straight line are related as $t=\sqrt{(x+1)(x-1)}.$ Its acceleration at a time $t$ is

A particle is projected from ground in vertical direction at $t=0.$ At $t=0.8 \mathrm{s},$ it reaches $h=14 \mathrm{m}.$ It will again come to same height at $t=? \left[g=10 {\mathrm{ms}}^{-2}\right]$ 

Three particles are projected upward with initial speeds $10 {\mathrm{ms}}^{-1}, 20 {\mathrm{ms}}^{-1}$ and $30 {\mathrm{ms}}^{-1}.$ The displacements covered by them in their last second of motion are $x_1, x_2$ and $x_3$ then

Which of the following graphs are wrong for a particle performing rectilinear motion, provided there is no collision any where