Which of the following may be the unit of power? A.J s b.kg / MS ^ 2 c.kg m ^ 2 / S ^ 3 d.kg m ^ 2 / S ^ 2 RT

Which of the following may be the unit of power? A.J s b.kg / MS ^ 2 c.kg m ^ 2 / S ^ 3 d.kg m ^ 2 / S ^ 2 RT

From power = work / time
Work = force x displacement P = f / S = MAS / T
C.kg m^2/s^3

What's the unit of G, N / kg or M / S ^ 2

The two units are the same
Newton's second law is f = ma
The unit of F is n
M is in kg
The unit of a is m / S ^ 2
So 1n = 1kg M / S ^ 2
So 1n / kg = 1m / S ^ 2
Many units in physics are the same, all derived from basic units

After selecting the unit of length as m, the unit of mass as kg and the unit of time as s, the units of all other physical quantities in mechanics can be derived
But according to the relevant formula, there is a physical quantity and its expression as a = root GM / R, where m is the mass, R is the distance, and the constant G = 6.67 * 10 ^ - 11n · m ^ 2 / kg ^ 2. A student speculates that a is the velocity. Do you think it is correct

Correct;
A = root GM / r = root (n * m ^ 2 / kg ^ 2 * kg / M) = root (m * n / kg)
=Root sign (m * m / S ^ 2) = m / S
This formula is obtained by using: MV ^ 2 / r = GMM / R ^ 2, and the simplified formula is: v = root sign (GM / R)