I would tell him, in the kindest, most gentle way I could manage,
to fahgeddaboudit.
The total amount of energy doesn't change. Energy is never created,
and it never disappears. If you have some energy, then it had to come
from somewhere, and if you used some energy, then it had to go
somewhere.
You can never get more energy out of the electromotor than you put into it,
and in the real world, you can't even get THAT much out, because some
of it is always used on the way through.
Pour yourself a cold glass of soda, then look up "Perpetual Motion" or
"Free Energy" on the internet, relax, and enjoy the show. They are all
fakes. They may not all be intentionally meant to fool you, but they are
all impossible.
Answer:
zero
rank the magnitude of the average velocity over the first 2 second
F = force applied to hold the weight of the bowling ball = weight of the bowling ball = 75 N
d = distance through which the bowling ball is moved horizontally = 10 meter
θ = angle between the force in vertically upward direction and displacement in horizontal direction = 90
W = work done on the bowling ball
work done on the bowling ball is given as
W = F d Cosθ
inserting the values
W = (75) (10) Cos90
W = (75) (10) (0)
W = 0 J
Answer:
greater
Explanation:
the speed of sound in steel is greater than water. the speed of sound in wood is not, In water, the particles are much closer together, and they can quickly transmit vibration energy from one particle to the next. This means that the sound wave travels over four times faster than it would in air, but it takes a lot of energy to start the vibration.
Wood is less dense and force can make a sound.
It is an example of reflection of wave. C.