If net charge on one object is doubled, then electric force will also get double. It is because they are directly proportional to each other.
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Answer:
The spring was compressed the following amount:

Explanation:
Use conservation of energy between initial and final state, considering that the surface id frictionless, and there is no loss in thermal energy due to friction. the total initial energy is the potential energy of the compressed spring (by an amount
), and the total final energy is the addition of the kinetic energies of both masses:



Answer:
Explanation:
Acceleration of particle A is 7.3 times the acceleration of particle B.
Let the acceleration of particle B is a, then the acceleration of particle A is
7.3 a.
Let the period of particle A is T and the period of particle B is 2.5 T.
Let the radius of particle A is RA and the radius of particle B is RB.
Use the formula for the centripetal force

So, 
The ratio of radius of A to the radius of B is given by


RA : RB = 1.17