Question

A car of 1000 kg starts to move from rest and travels a distance of 150 m in 10 second. How much force is needed?​

Answer 1

• Initial velocity=u=0m/s
• Distance=s=150m
• Time=t=10s
• Acceleration=a

Using second equation of kinematics

$\\ \sf\longmapsto s=ut+\dfrac{1}{2}at^2$

$\\ \sf\longmapsto 150=0(10)+\dfrac{1}{2}a(10)^2$

$\\ \sf\longmapsto 150=\dfrac{1}{2}\times 100a$

$\\ \sf\longmapsto 50a=150$

$\\ \sf\longmapsto a=\dfrac{150}{50}$

$\\ \sf\longmapsto a=3m/s^2$

• Mass=m=1000kg
• Force=F

Using newtons second law

$\\ \sf\longmapsto F=ma$

$\\ \sf\longmapsto F=1000(3)$

$\\ \sf\longmapsto F=3000N$