Efficiency = (Wanted) energy out ÷ energy in × 100
Energy in = 400J
Wanted Energy out = 240J
Energy cannot be used up, only transferred, so the remaining energy is most likely to be transferred into unwanted energy (loss of energy) such as heat energy.
Efficiency = 240 ÷ 400 × 100
Efficiency = 0.6 × 100
Efficiency = 60%
Answer:
The answer is B
Explanation:
Because when the both sides aren't balanced one side has to cause motion. (fall down)
1,000 grams = 1 kilogram
20 grams = 0.02 kilogram
Kinetic energy = (1/2) (mass) x (speed)²
(1/2) (0.02) x (15)² =
(0.01) x (225) = 2.25 joules
Answer:
use the bowl of water because Earth's magnetic field is relatively weak. Allowing it to float freely on the water, allows the magnetized needle to freely react to Earth's magnetic field, causing it to align North to South. If you watched closely, the same end of the needle should always point to the North
Explanation:
Answer:
P = 14700 J
Explanation:
Given that,
Mass of a piano, m = 75 kg
It is delivered throughout the window of a 6th story apartment which is 20 m above the ground.
We need to find the potential energy of the piano. It is given by :
P = mgh
Putting all the values,
P = 75 kg × 9.8 m/s² × 20 m
P = 14700 J
So, the potential energy of the piano is 14700 J.
