Explanation:
The mass of a ball, m = 2 kg
It is traveling with a speed of 10 m/s
The ball's kinetic energy just as it leaves the boy's hand is calculated as follows :

The ball's kinetic energy just as it leaves the boy's hand is 100 J. The potential energy of the ball when it reaches the highest point is same as the kinetic energy as it leaves the boy's hand.
Hence, the required kinetic and potential energy is 100 J.
Answer:
1. 310 N
2. 310 N
Explanation:
1. Determination of the net force.
Force applied (Fₐ) = 430 N
Force experience (Fₑ) = 120 N
Net force (Fₙ) =?
Fₙ = Fₐ – Fₑ
Fₙ = 430 – 120
Fₙ = 310 N
Hence, the net force acting on the crate is 310 N
2. Determination of the net force.
Force applied (Fₐ) = 375 N
Force of friction (Fբ) = 65 N
Net force (Fₙ) =?
Fₙ = Fₐ – Fբ
Fₙ = 375 – 65
Fₙ = 310 N
Hence, the net force acting on the crate is 310 N.
Answer:
The mechanism of energy transport through a medium involves the absorption and reemission of the wave energy by the atoms of the material. When an electromagnetic wave impinges upon the atoms of a material, the energy of that wave is absorbed.
Answer: 
Explanation:
Given
mass of sled m=5 kg
Elevation 
(coefficient of kinetic friction)
Friction will oppose the motion of the sled while sled weight sin component helps it to move down the incline

Substituting values
