Linear Impulse and Momentum Problem No.1

The 100-kg crate shown is originally at rest on the smooth horizontal surface. If a force of 200 N, acting at an angle of 45°, is applied to the crater for 10-s, determine the final velocity of the crate and the normal force which the surface exerts on the crate during the time interval.

Figure

Solution:

• Construct a free-body diagram

• Given:
• Mass = 100 kg
• Force = 200 N
• V₁= 0
• t₁ = 0
• t₂ = 10 s
• Find V₂ and N

Working equation:

Substitute the given values:

Then, we can find the value of the velocity:

For the value of normal force (N), find first the value of W:

Then,