Answer:
B. When the racket hits the tennis ball with a force, the tennis ball applies an equal but opposite force to the racket.
Explanation:
According to the Newton's third law of motion every action has equal and opposite reaction. So, when the force is applied by the racket on the ball then the ball also applies an equal intensity of force in the opposite direction on the racket. It is just that the the force on the racket is absorbed by the player holding it.
Electric potential energy is defined as Ep=Q*V where Q is the magnitude of the charge and V is the potential difference. So when a charge moves between the points that have a potential difference, it's energy changes.
In our case:
Q=2e=2*(-1.6*10^-19) C
V=75 V
Ep=(-3.2*10^-19)*75
Ep=-2.4*10^-17 J
The change in potential energy of the charge is -2.4*10^-17 J
Answer:
In a house there is a lot less space so there is no where for the sound to travel, but if you are outside there is a lot more space so therefore, the sound can travel anywhere.
Explanation:
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