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 3 m. Assuming that the resistance due to water is negligible, what will be the speed of the ship ?

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

Answer 1

The correct option is A 0.1 m/s

Given,

Mass of ship, $M=3\times {10}^{7}kg$

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

Distance, $s=3m$

Acceleration, $a=\frac{F}{M}=\frac{5\times {10}^4}{3\times {10}^7}=\frac{1}{600}m{s}^{-2}$

Apply kinematic equation of motion

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

$v=\sqrt{2as}=\sqrt{2\times \frac{1}{600}\times 3}=0.1m{s}^{-1}$

Hence, velocity of ship $0.1m{s}^{-1}$