Answer:
The velocity of the skateboard is 0.774 m/s.
Explanation:
Given that,
The spring constant of the spring, k = 3086 N/m
The spring is stretched 18 cm or 0.18 m
Mass of the student, m = 100 kg
Potential energy of the spring, 
To find,
The velocity of the car.
Solution,
It is a case of conservation of energy. The total energy of the system remains conserved. So,






v = 0.774 m/s
So, the velocity of the skateboard is 0.774 m/s.
A substance changes from liquid to gas
Answer:
Control rods
Explanation:
Control rods is unique to nuclear power plants as they are mainly used in nuclear reactors to stabilize the rate of fission of plutonium or uranium. They are usually composed of chemical elements such as cadmium, silver, boron, and indium.
Who created the theory of general relativity?:
The answer would be: Albert Einstein.
Albert Einstein developed the general relativity theory (gravitation).
The year he developed the general relativity theory or (GR) was back in 1907 and 1915. Then many other contributions after 1915.
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