Answer:
U = 1000 J
Explanation:
By the conservation of energy, potential energy is converted into kinetic energy when the ball falls from a height.
U = Energy (in Joules)
m = mass (in kg)
v = velocity in (m/s)
g = acceleration due to gravity (in m/s^2)
h = height (in m)
Let's use 
as we have the values given.
The correct answer to the question is C i.e C represents the friction from air resistance.
EXPLANATION:
Before coming into any conclusion, first we have to understand friction.
The friction is the opposing force which acts tangentially between two bodies in contact when there is a relative motion between them.
The air resistance is that frictional force which is provided by the air to the moving body through it. Hence, the friction from air resistance will be directed opposite to the motion of the body.
In the given diagram, the airplane is going horizontally. The force A acts in forward direction while force C acts in backward direction. The forces B and D are acting vertically. There is no motion in vertical direction. Hence, the net force of A and C will cause the airplane to move.
As the plane is moving along the direction of A, the frictional force must act along the direction of C.
Answer:
D
Explanation:
They looked at her hand and made a formal conclusion from that
well thanks for the Information
