Failed experiments, uncontrolled variables, invalid data, and generalized human error
Gravitational energy is a form of potential energy because it is dependent on the mass of an object and needs to be calculated for the specific object.
Answer:
A- Astronomical body
C- Galaxy
D- Comet
B- Moon
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Answer:
So coefficient of kinetic friction will be equal to 0.4081
Explanation:
We have given mass of the block m = 0.5 kg
The spring is compressed by length x = 0.2 m
Spring constant of the sprig k = 100 N/m
Blocks moves a horizontal distance of s = 1 m
Work done in stretching the spring is equal to 
This energy will be equal to kinetic energy of the block
And this kinetic energy must be equal to work done by the frictional force
So 


So coefficient of kinetic friction will be equal to 0.4081