The dome of a van de graaff generator has a diameter of 30 cm and is at a potential of +20 000v. calculate : a) the charge on the dome b) the electric field strength at the surface of the dome c) the force on a proton near the surface of the dome

a) radius of the dome r=15 cm

Potential, V=20,000 V

here Q is charge, is permitivity of vacuum and r is the distance from the charge.

b) Electric field (E) strength at the surface of the dome is given by:

c)force on the proton near the surface of the dome:

where E is the electric field and q is the charge of proton.

charge of a proton

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day