Question

An object of 30 kg is moved with a velocity of 2 m/s on a horizontal smooth surface. What is the velocity of the block for 4 seconds if force of 40 N is applied on it in the direction of force?

Answer 1

given
F=40N
m=30kg
then a = F/m
         a= 40/30 = 4/3 m/s^2
V=u+at
  =2+ 4/3 x 4
  = 22/3

Answer 2

The velocity of the block is 7.33 m/s.

Step-by-step Explanation:

Given:

Mass of object $= 30 kg$.

It is moved with a velocity  $2 m/s$ on a horizontal smooth surface.

The force applied on it in the direction of force is $40 N$.

To find: The velocity of the block for 4 seconds if a force of 40 N is applied in the force's direction.

Formula used:

Force x time = mass (final velocity – initial velocity)

Solution:

$(40$×$4) = 30 (v - 2)$

$160=30V-60$

now switch the sides

$30V-60=160$

Add $60$ to both sides

$30V-60+60=160+60$

$30V=220$

Now divide both sides by $30$.

we get $V=\frac{22}{3}$

That is $V=7.33m/s$

Hence, The block's velocity for 4 seconds if a force of 40 N is applied in the force direction is 7.33 m/s.