Answer:
The potential energy (P.E) at the top is 392 J
The kinetic energy (K.E) at the top is 0 J
The potential energy (P.E) at the halfway point is 196 J.
The kinetic energy (K.E) at the halfway point is 196 J.
Explanation:
Given;
mass of the rock, m = 2 kg
height of the cliff, h = 20 m
speed of the rock at the halfway point, v = 14 m/s
The potential energy (P.E) and kinetic energy (K.E) when its at the top;
P.E = mgh
P.E = (2)(9.8)(20)
P.E= 392 J
K.E = ¹/₂mv²
where;
v is velocity of the rock at the top of the cliff = 0
K.E = ¹/₂(2)(0)²
K.E = 0
The potential energy (P.E) and kinetic energy (K.E) at the halfway point;
P.E = mg(¹/₂h)
P.E = (2)(9.8)(¹/₂ x 20)
P.E = 196 J
K.E = ¹/₂mv²
where;
v is velocity of the rock at the halfway point = 14 m/s
K.E = ¹/₂(2)(14)²
K.E = 196 J.
Answer:
Acceleration 
Explanation:
We have given that the force by the motor 
Resistive force by the water 
So net force 
Mass of the boat = 1384.1 kg
According to newton's second law F=Ma, here M is mass and a is acceleration
So 

When matter changes state, many people think it goes from solid to liquid to gas, or vise versa. But the true fact is, matter doesn't change in any order.
Answer:The atmosphere directly absorbs about 23% of incoming sunlight, and the remaining energy is transferred from the Earth's surface by evaporation (25%), convection (5%), and thermal infrared radiation (a net of 5-6%).Jan
Explanation:
None