Answer:
W = 20 J
Explanation:
Given that,
The mass of a loaded sack, m = 1000 g = 1 kg
It falls down from the floor of a lorry 200 cm high, h = 2 m
We need to find the work done by the gravity. The work done by an object under the action of gravity is given by :
W = mgh
Substitute all the values,
W = 1 × 10 × 2
= 20 J
Hence, the required work done by gravity is equal to 20 J.
Player A needs the least amount of energy. The ball is light weight and she is closest to the goal so the momentum need to kick the ball will be the least and the distance is has to travel is the shortest. But player C needs the most amount of energy. The ball is heavy so it will take the most momentum to move the ball and over such a long distance. Hope this help idrk.
The angle of the wedge is 30°.
Answer:
5.88 ft/s
Explanation:
a) The block will slide down due to it's weight.
initial velocity u= 0
final velocity, v
acceleration, a = g sin 30° = 32 ft/s²× sin 30° = 16 ft/s²
Sliding displacement, s = 3ft
Use third equation of motion:

substitute the values and solve for v

b) Use conservation of momentum:
Initial momentum of the system = 0
final momentum = (15) ( 9.8)+ (25)(v')
v' = 5.88 ft/s
Chemical energy is transformed in your body
The given question is incomplete. The complete question is as follows.
A 75-g bullet is fired from a rifle having a barrel 0.540 m long. Choose the origin to be at the location where the bullet begins to move. Then the force (in newtons) exerted by the expanding gas on the bullet is
, where x is in meters. Determine the work done by the gas on the bullet as the bullet travels the length of the barrel.
Explanation:
We will calculate the work done as follows.
W = 
= 
= ![[14000x + 5000x^{2} - 8666.7x^{3}]^{0.54}_{0}](https://tex.z-dn.net/?f=%5B14000x%20%2B%205000x%5E%7B2%7D%20-%208666.7x%5E%7B3%7D%5D%5E%7B0.54%7D_%7B0%7D)
= 7560 + 1458 - 1364.69
= 7653.31 J
or, = 7.65 kJ (as 1 kJ = 1000 J)
Thus, we can conclude that the work done by the gas on the bullet as the bullet travels the length of the barrel is 7.65 kJ.