4N force applied on a body mass 20kg then calculate work done in 3sec?

To calculate the work done, we need to use the formula:

Work = Force × Distance

In this case, we know the force applied (4N) and the time for which the force is applied (3 sec), but we need to find the distance.

To calculate the distance, we can use Newton's second law of motion:

Force = Mass × Acceleration

Since the mass (m) of the body is given as 20kg, and assuming the body is initially at rest, we can rearrange the formula to find the acceleration (a):

Acceleration = Force / Mass

Substituting the values, we get:

Acceleration = 4N / 20kg

Now, we can use one of the constant acceleration equations:

Distance = (1/2) × Acceleration × Time^2

Plugging in the values, we have:

Distance = (1/2) × (4N / 20kg) × (3 sec)^2

Simplifying further:

Distance = (1/2) × (0.2m/s^2) × 9s^2

Distance = (1/2) × 1.8m

Distance = 0.9m

Now, we can calculate the work done using the formula:

Work = Force × Distance

Work = 4N × 0.9m

Work = 3.6 Joules

So, the work done is 3.6 Joules.

work = force * distance so how far?

assume v =0 at start

F = m a
4 = 20 a
a = (1/5) m/s^2

v = Vi + a t
v = 0 + 3 a

x = Xi + Vi t + (1/2) a t^2
x = 0 + 0 + (1/2)(9)
x = 4.5 meters

so
W = F x = 4 * 4.5
= 18 Joules