Question

A ship of mass $3\times {10}^{7}kg$ initially at rest is pulled by a force of $5\times {10}^{4}N$ through a distance of $3m$. Assuming that the resistance due to water is negligible, what will be the speed of the ship?

• A. $0.1m/s$
• B. $1.5m/s$
• C. $5m/s$
• D. $0.2m/s$

Answer 1

The correct option is A $0.1m/s$

Given,

$m=3\times {10}^{7}kg$

$S=3m$

$u=0m/s$

$F=5\times {10}^{4}N$

Newton 2nd law,

$F=ma$

$a=\frac{F}{m}=\frac{5\times {10}^4}{3\times {10}^7}$

$a=1.66\times {10}^{-3}m/s^2$

Kinematics 2nd equation of motion,

$2as=v^2-u^2$

$2\times 3\times 1.66\times {10}^{-3}=v^2$

$v=0.1m/s$

The correct option is A.