I attached the full question.
We know that for a parallel-plate capacitor the surface charge density is given by the following formula:

Where V is the voltage between the plates and d is separation.
Voltage is by definition:

Voltage is analog to the mechanical work done by the force.
Above formula is correct only If the field is constant, and we can assume that it is since no function has been given.
The charge density would then be:

Please note that elecric permittivity of air is very close to elecric permittivity of vacum, it is common to use them <span>interchangeably</span>.
Answer:
5. Quadruple
Explanation:
The electrostatic force between two charged particles is given by:

where
k is the Coulomb's constant
q1, q2 are the two charges
r is the separation between the charges
If the distance between the charges is reduced to half,

So the new force will be

So, the force will quadruple.
I would say the plastic grip because glass, wood, and plastic are all good conductors of electricity
Answer: Tides are periodic rises and falls of large bodies of water. Tides are caused by gravitational interaction between the earth and the moon. The gravitational attraction of the moon causes the oceans to bulge out in the direction of the moon.
Answer:
C
Explanation:
horizintal speed stays same
only vertical speed changes
so H speed will stay 30 m/s