Answer: when the ball moves to the east
Explanation:
Work is done when an external force makes an object move in the direction that it was forcing it to by transferring energy to it.
The wind is blowing to the east which means that it is exerting a force that is trying to move the ball to the east. For work to actually occur, the ball needs to move in the direction of the force being applied which is the east.
The correct answer is D: mass!
Answer:
z = 0.8 (approx)
Explanation:
given,
Amplitude of 1 GHz incident wave in air = 20 V/m
Water has,
μr = 1
at 1 GHz, r = 80 and σ = 1 S/m.
depth of water when amplitude is down to 1 μV/m
Intrinsic impedance of air = 120 π Ω
Intrinsic impedance of water =
Using equation to solve the problem
E(z) is the amplitude under water at z depth
E_o is the amplitude of wave on the surface of water
z is the depth under water
now ,
taking ln both side
21.07 x z = 16.81
z = 0.797
z = 0.8 (approx)
Kinetic energy = 1/2mv^2
=1/2(25)(1^2)
= 12.5J
Answer: I think it's false
because light travels slower in dense area's.