Motion In A Straight Line - Mechanics - Physics Previous Year Questions

The ratio of times taken by a freely falling body to travel first 5 m , second 5 m , third 5 m distances is

The driver of a bus moving with a velocity of $72 \mathrm{~km} / \mathrm{h}$ observes a boy walking across the road at a distance of 50 m in front of the bus and decelerates the bus at $5 \mathrm{~ms}^{-2}$ by applying brakes and is just able to avoid an accident. The reaction time of the driver is

The initial and final velocities of a body projected vertically from the ground are $20 \mathrm{~ms}^{-1}$ and $18 \mathrm{~ms}^{-1}$ respectively. The maximum height reached by the body is (Acceleration due to gravity $=10 \mathrm{~ms}^{-2}$ )

A person wearing a parachute jumps off a plane from a height of 2 km from the ground and falls freely for 20 m before his parachute opens. After his parachute opens if he continues to move uniformly with the velocity attained due to his freefall, the total time taken by the person to reach the ground is (Acceleration due to gravity $=10 \mathrm{~ms}^{-2}$ )

A particle initially at rest is moving along a straight line with an acceleration of $2 \mathrm{~ms}^{-2}$. At a time of 3 s after the beginning of motion, the direction of acceleration is reversed. The time from the beginning of the motion in which the particle returns to its initial position is

For a particle moving along a straight line path, the displacements in third and fifth seconds of its motion are 10 m and 18 m respectively. The speed of the particle at time $t=4 \mathrm{~s}$ is

The relation between the displacement ' $x$ ' (in metre) and the time ' $t$ ' (in second) of a particle is $t=2 x^2+3 x$. If the displacement of the particle is 25 cm from the origin $(x=0)$, then the acceleration of the particle is