Question

A constant force acts on an object of mass 5 kg for a duration of 2 seconds .It increases the objects velocity from 3 m/s to 7 m/s. Find the magnitude of the applied force . Now if the tax were applied for a duration of 5 seconds , what would be the final velocity of the object?

Answer 1

Given,

$mass=5kg$

$t_1=2s$

Initial velocity $u=3m/s$

Final velocity $v=7m/s$

$t_2=5s$

So,

Let the Force be $F$

Let the acceleration be $a$

So,

$a=\frac{(v-u)}{t}=\frac{(7-3)}{2}=2m/s^2$

So the magnitude of the applied force is $10N$

And the final velocity after $5s$ is $v$

So,

$v=u+at$

$v=3+2\times 5$

$v=13m/s$

The final velocity after $5s$ is $13m/s$