Question

A 150 kg windonpane falls from the side of a bailing. During the last 15 m of its decent its speed increases by 7.2 m/s. If there was a constant force of air resistance of 85 N, how fast was it travelling just before it hit the ground?

Answer 1

To find the speed of the windowpane just before it hits the ground, we use the equation v^2 = u^2 + 2as. The final velocity is approximately 14.28 m/s.

Step-by-step explanation:

To find the speed of the windowpane just before it hits the ground, we need to calculate its final velocity.

We can use the equation v^2 = u^2 + 2as, where v is the final velocity, u is the initial velocity, a is the acceleration, and s is the distance traveled.

Given that the mass of the windowpane is 150 kg, the air resistance is 85 N, and the distance traveled is 15 m, we can rearrange the equation to solve for v:

v^2 = 0^2 + 2(85/150)(15)

v^2 ≈ 204

v ≈ √204 ≈ 14.28 m/s

Therefore, the windowpane was traveling at approximately 14.28 m/s just before it hit the ground.