Question

A proton and an electron are released from rest at the same time from the midpoint between two charged parallel plates. The plates are charged with equal surface charge densities of opposite signs. Ignore the interaction between the electron and the proton and consider only the interaction of each charge with the electric field of the plates. After being released, the proton will accelerate toward the negative plate, and the electron will accelerate toward the positive plate.

a)

Which charge will reach the plate first?

the proton

the electron    

They will both reach the plate at the same time.

If t_p and t_e are the times taken for the proton and electron to reach the plate, calculate the ratio

t_p

t_e

.b)

Which charge hits the plate moving the fastest?

the proton

the electron    

They both reach the plate at the same speed.

If v_p and v_e are the speeds of the proton and electron as they hit the plate, calculate the ratio

v_p

v_e

.

Answer 1