Let the sphere is having charge Q and radius R
Now if the proton is released from rest
By energy conservation we can say



now take square root of both sides

so the proton will move by above speed and
here Q = charge on the sphere
R = radius of sphere

Answer:B
Explanation:
Given
speed of car 
mass of clump 
Radius of car tire 
Since the tire is rotating about axle so a centripetal force is acting constantly on each particle towards the center of tire.
Centripetal force is given by

where 



(inward)
Explanation:
Using Ohm's Law and a bit of substitution, we can use voltage divided by current to solve for resistance. Doing that, we'll get 6 Ohm.
V = I · R
Voltage = (current) · (Resistance)
Voltage = (250 A) · (2.09 x 10⁴)
Voltage = 5,225,000 volts .
I may be out of line here, but I'm pretty sure
that the resistance is 2.09 x 10⁻⁴ .
Then
Voltage = 0.05225 volt (not 5 million and something)