Answer:

Explanation:
We are given that a parallel- plate capacitor is charged to a potential difference V and then disconnected from the voltage source.
1 m =100 cm
Surface area =S=


We have to find the charge Q on the positive plates of the capacitor.
V=Initial voltage between plates
d=Initial distance between plates
Initial Capacitance of capacitor

Capacitance of capacitor after moving plates


Potential difference between plates after moving








Hence, the charge on positive plate of capacitor=
Answer:
Acceleration of the proton will be equal to 
Explanation:
We have given electric field 
Mass of proton is equal to 
And charge on proton is equal to 
Electrostatic force will be responsible for the motion of proton
Electrostatic force will be equal to 
According to newton law force on the proton will be equal to F = ma, here m is mass of proton and a is acceleration
This newton force will be equal to electrostatic force
So 

So acceleration of the proton will be equal to 
Answer:
D. 3 psi
Explanation:
Pressure is defined as force acting per unit area and is numerically expressed as:

where P represent pressure, F is force and A is area where the force acts. Substituting 300 lb for force and 100 sq.in for area then pressure,

Therefore, from the choices given, option D, 3psi is the right choice.
Answer:
A jack is used to <u>lift</u> the force.
I think that's the answer. I don't really understand the question.