There are two ways to solve this problem. First we write the given.
Given: Force F = 400 N; Height h = 0.5 m; Time t = 2 s
Formula: P = W/t; but Work W = Force x distance or W = f x d
Weight is also a Force, therefore: W = mg, solve for Mass m = ?
m = w/g m = 400 N/9.8 m/s² m = 40.82 Kg
P = W/t = F x d/t = mgh/t P = (40.82 Kg)(9.8 m/s²)/2 s
P = 100 J/s or 100 Watts
The time in air is determined by the initial vertical velocity. This is because, the steeper the launch angle the larger the vertical velocity component, that causes the launch angle to increase the time in air.
I did Physics a while ago but I believe my answer is correct. (:
Hope this helps! (:
Answer:
17 m/s south
Explanation:
= Mass of dog = 10 kg
= Mass of skateboard = 2 kg
v = Combined velocity = 2 m/s
= Velocity of dog = 1 m/s
= Velocity of skateboard
In this system the linear momentum is conserved
The velocity of the skateboard will be 17 m/s south as the north is taken as positive
