V K Sally and R Goel Solutions for Chapter: Force and Laws of Motion, Exercise 8: EXERCISE

Name and define the unit of force in SI system ?

Why does a player move his hands backward while taking a catch? Explain.

Prove mathematically: $\mathrm{F}=\mathrm{ma}$, where $\mathrm{F}$is the force impressed on a body, $\text{'}\mathrm{m}\text{'}$ the mass and $\text{'}a\text{'}$ the acceleration.

Velocity versus time graph of a ball of mass $50 \mathrm{g}$ rolling on a concrete floor is shown in figure. Calculate the acceleration and frictional force of the floor on the ball.

A truck of mass $M$ is moved under a force $F$. If the truck is then loaded with an object equal to the mass of the truck and the driving force is halved, then how does the acceleration change ?

Using second law of motion, derive the relation between force and acceleration. A bullet of $10 \mathrm{g}$ strikes a sand-bag at a speed of ${10}^3 {\mathrm{ms}}^{-1}$ and gets embedded after travelling $5 \mathrm{cm}$. Calculate 
(i) the resistance force exerted by the sand on the bullet. 
(ii) the time taken by the bullet to come to rest.

Derive the unit of force using the second law of motion. A force of $5 \mathrm{N}$ produces an acceleration of $8 {\mathrm{ms}}^{-2}$ on a mass $m_1$ and an acceleration of $24 {\mathrm{ms}}^{-2}$ on a mass $m_2$. What acceleration would the same force provide if both stones are tied together?

What is momentum? Write its SI unit. Interpret force in terms of momentum? Represent the following graphically.

(a) Momentum versus velocity when mass is fixed.

(b) Momentum versus mass when velocity is constant.