We can calculate this with the law of conservation of energy. Here we have a food package with a mass m=40 kg, that is in the height h=500 m and all of it's energy is potential. When it is dropped, it's potential energy gets converted into kinetic energy. So we can say that its kinetic and potential energy are equal, because we are neglecting air resistance:
Ek=Ep, where Ek=(1/2)*m*v² and Ep=m*g*h, where m is the mass of the body, g=9.81 m/s² and h is the height of the body.
(1/2)*m*v²=m*g*h, masses cancel out and we get:
(1/2)*v²=g*h, and we multiply by 2 both sides of the equation
v²=2*g*h, and we take the square root to get v:
v=√(2*g*h)
v=99.04 m/s
So the package is moving with the speed of v= 99.04 m/s when it hits the ground.
When work is done and a force is transferred an object must move
Answer:
a) N = 343 [N]
Explanation:
We must remember Newton's third law, which tells us that the force acting on a body is equal to the normal reaction force of equal magnitude but acting in the opposite direction.
where:
m = mass = 35 [kg]
g = gravity acceleration = 9.81 [m/s²]
![N = 35*9.8\\N= 343 [N]](https://tex.z-dn.net/?f=N%20%3D%2035%2A9.8%5C%5CN%3D%20343%20%5BN%5D)
Answer:
15.88m/s
Explanation:
At the top of the roller coaster you will have three forces acting on the roller-coaster. See the image below. Fc is the centripetal force (for an object in circular motion), Fg is the gravitational force, and Fn is the normal force. To achieve the minimum speed we assume the roller-coaster is barely touching the vertical loop and so the normal force is zero. This leaves two acting forces.
Average speed = (distance traveled) / (time to cover the distance)
= (35 yards) / (3.8 seconds)
= 9.21 yards per second
