Answer to Question #301274 in Physics for waren

Question

A BODY AT REST IS TO BE ACCELERATED BY A CONSTANT

FORCE SO THAT IT WILL HAVE A VELOCITY OF 800 CM/S

AFTER EXACTLY 8 S. FIND THE FORCE IF THE BODY WEIGHS 490

DYNES.

Answer 1

Given:

$\Delta v=8\:\rm m/s$

$\Delta t=8\:\rm s$

$mg=490*10^{-5}\:\rm N$

The force

$$F=m\frac{\Delta v}{\Delta t}\\ =(490*10^{-5}/9.8)*\frac{8}{8}=5*10^{-4}\:\rm N=50\: dynes$$