Question

class 9 questions of physics.
chapter- force and laws of motion​

Answer 1

$\huge\sf\pink{\boxed{HEY\:USER}}$

$\huge\sf\blue{\boxed{ANSWER}}$

Here,

$\implies\sf\blue{DISTANCE\: TRAVELLED,S=400M}$

$\implies\sf\blue{Initial\:velocity=0m/s^-1}$

$\implies\sf\red{TIME=20s}$

$\implies\sf\pink{ACCELERATION=?}$

$\text{USING THE SECOND EQUATION OF MOTION}$

$\tt\blue{S=ut+1/2 at^2}$

$\implies\tt\blue{400=0m/s^-1×20+/frac{1}{2}a×(20s)^2}$

$\implies\sf\pink{400m=a×200s}$

$\implies\sf\blue{a=2m/s^2}$

Now,

We have to collect the force by using relation

$\large\sf\blue{F=ma}$

Here, m=7metric =7000kg

$\huge\sf\red{F=7000×2m/s^2=14000N}$

Thank You!