Embibe Experts Solutions for Chapter: Newton’s Laws of Motion, Exercise 1: BITSAT 2017

A body of mass $m$ is moving in a straight line with momentum $p$. Starting at time $t=0$, a force $F=at$ acts in the same direction on the moving particle during time interval of $T$. So that its momentum changes from $p$ to $2p$. The value of $T$ is

A maximum of $3 \mathrm{N}$ force can be applied on a block, down the incline, that would still not move the block which is placed on a rough inclined plane as shown in the figure. The maximum external force up the inclined plane that does not move the block is $12 \mathrm{N}$. The coefficient of static friction between the block and the plane is $\left[\mathrm{Take} g=10 \mathrm{m} {\mathrm{s}}^{-2}\right]$

The force on a body of mass $1 \mathrm{kg}$ is $\left(20 \hat{\mathrm{i}}+10 \hat{\mathrm{j}}\right) \mathrm{N}$. If it starts from rest, then the position of the body at time $t=2 \mathrm{s},$ is

An automobile moving with a speed of $36 \mathrm{km} {\mathrm{h}}^{-1}$ reaches an upward inclined road of angle $30°,$ its engine becomes switch off. If the coefficient of friction is $0.1$, then how much distance will automobile move before coming to rest?

An object takes $n$ times as much time to slide down a $45°$ rough inclined plane as it takes to slide down a perfectly smooth $45°$ inclined plane. The coefficient of kinetic friction between the rough plane and the object is

A pulley of radius $2 \mathrm{m}$ is rotated about its axis by a force $=\left(20t-5t^2\right)$ newton (where $t$ is measured in seconds) applied tangentially. If the moment of inertia of the pulley about its axis of rotation is $10 \mathrm{kg} {\mathrm{m}}^2,$ the number of rotation made by the pulley before its direction of motion is reversed is

Two blocks $A$ and $B$ are placed one over the other on a smooth horizontal surface. The maximum horizontal force that can be applied on lower block $A$, so that $A$ and $B$ move without separation is $49 \mathrm{N}$. The coefficient of friction between $A$ and $B$ is

A block $A$ of mass $100 \mathrm{kg}$ rests on another block $B$ of mass $200 \mathrm{kg}$ and is tied to a wall as shown in the figure. The coefficient of friction between $A$ and $B$ is $0.2$ and that between $B$ and ground is $0.3$. The minimum force required to move the block $B$ is $\left(g=10 \mathrm{m} {\mathrm{s}}^{-2}\right)$