Answer:
ball will oscillate in between the plates
Explanation:
The metallic coated styrofoam lowered in between two large metal plates, a large potential difference V is kept between the two plates, will experience a force of repulsion ( because both plates and balls will have similar kind of charges and like charges repel each other) from the opposite plates.
If we consider d as the distance between the plates, E as electric field because of Potential difference V. Then force F experience by the ball will be

where q be the total charge on the metallic coated ball.
clearly, since, both the plates will repel the ball in opposite directions, hence ball will be in oscillate in between the plates.
Mass of the dart = 0.01 kg
Speed at which the dart is thrown = 20 m/s
Kinetic Energy = (1/2) * mass * speed * speed
= (1/2) * (0.01) * (20) * (20) Joules
= (400 *0.01)/2 Joules
= 4/2 Joules
= 2 Joules
So the kinetic energy of the dart is 2 Joules. I hope this is the correct answer and it has helped you.
It's commonly referred to as an electric current.
Answer:
Save the file and try to put stuff over the file. (kinda off like a picture)