Answer:
-100N
Explanation:
Newton's third law of motion states that to every force exerted on one body, there is an equal and opposite force. This means that if object A exerts an ACTION force on B, there is a force called REACTION FORCE, which is equal and opposite, exerted on A by B.
The action and reaction forces are equal in size/magnitude but opposite in direction. In this case where a tennis racket strikes a tennis ball with a force (action force) of 100N, the ball will strike the racket with a reaction force of -100N.
F(RB) = -F(BR)
Answer:
The equation for the object's displacement is 
Explanation:
Given:
m = 16 lb
δ = 3 in
The stiffness is:

The angular speed is:

The damping force is:

Where
FD = 20 lb
u = 4 ft/s = 48 in/s
Replacing:

The critical damping is equal:

Like cc>c the system is undamped
The equilibrium expression is:

Answer:
ε = 6.617 V
Explanation:
We are given;
Number of turns; N = 40 turns
Diameter;D = 18cm = 0.18m
magnetic field; B = 0.65 T
Time;t = 0.1 s
The formula for the induced electric field(E.M.F) is given by;
ε = |-NAB/t|
A is area
ε is induced electric field
While N,B and t remain as earlier described.
Area = π(d²/4) = π(0.18²/4) = 0.02545
Thus;
ε = |-40 × 0.02545 × 0.65/0.1|
ε = 6.617 V
(we ignore the negative sign because we have to take the absolute value)