Around 80 percent of the mass of the universe is made up material known as "Dark matter". It does not emit light or energy but the influence of it can be detected or observed gravitationally. Motions of stars and galaxy tell us how much mater there is, but somehow the speed of rotation of galaxy does not add up to its mass alone, there is a certain amount of matter really not accounted for. Dark matter maybe made up of non-baryonic matter, or perhaps what scientist called the WIMPS or (weakly interacting massive particles.)
Answer:
Ratio = 1:1
Explanation:
= initial momentum of the system
= final momentum of the system
For the momentum to be conserved , final total momentum must be equal to initial total momentum, so we have

Dividing both side by
, we get

hence
Ratio = 1
Generators take mechanical and output energy. electric motors take the input of electricity.
The acceleration of gravity on Earth is 9.8 m/s². That means that
an object falling under the influence of gravity will move 9.8 m/s
faster than it was moving a second earlier.
Falling from rest, it will be moving 9.8 m/s after the first second,
and 19.6 m/s after the 2nd second.
The height from which it fell doesn't matter.
The answer is A. it is the flow of electric charge. Current in electric circuits is carried by moving electrons in a wire. The current can also be carried by ions in electrolyte. Ampere is the SI unit for measuring an electric current. The electric current is measured using an equipment called ammeter.