Answer:
the circuit must be closed
Explanation:
Answer:
The question is incomplete. However, I believe, it is asking for the acceleration of the elevator. This is 3.16 m/s².
Explanation:
By Hooke's law, 
F is the force on a spring, k is the spring constant and e is the extension or compression.
From the question,

This is the force on the mass suspended on the spring. Its acceleration, a, is given by



This acceleration is more than the acceleration due to gravity, g = 9.8 m/s². Hence the elevator must be moving up with an acceleration of
12.96 - 9.8 m/s² = 3.16 m/s²
The gravitational potential energy of the system will decreases from 1,250 J to 625 J. Option A is corect.
<h3>What is the law of conservation of energy?</h3>
According to the Law of Conservation of Energy, energy can neither be created nor destroyed, but it can be transferred from one form to another.
The total energy is the sum of all the energies present in the system. The potential energy in a system is due to its position in the system.
TE=KE+GPE
Case 1;
1450 = 200 J+GPE
GPE=1450 -200
GPE=1250 J
Case 2;
1450 = 825 J+GPE
GPE=1450 -825
GPE=625 J
The gravitational potential energy of the system will decreases from 1,250 J to 625 J.
Hence, option A is corect.
To learn more about the law of conservation of energy, refer to brainly.com/question/2137260.
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Force is calculated F=m×a.
If both ships speed up with the same force, but have a different mass, This means that a also has to be different. If F is the same but ship a has a bigger mass(m) than ship b, then the acceleration(a) of ship b has to be bigger so F of each ship is the same. So the ship with the smaller mass will speed up faster.
The time of a wave is 65 m/sec. if the wavelength of the wave is 0.8 meters. what is the speed of this wave?
answer- the speed is 52