Part a: how many excess electrons must be distributed uniformly within the volume of an isolated plastic sphere 26.0cm in diameter to produce an electric field of 1500 n/c just outside the surface of the sphere? part b: what is the electric field at a point 13 cm outside of the surface of the sphere?

Q = 28.17 x 10⁻¹⁰ C

E= 375 N/C

Explanation:

Let Q be the charge on plastic sphere.

Field on the surface =k x charge / radius²

Putting the values we get

Q = 28.17 x 10⁻¹⁰ C

No of electrons = Charge / charge on one electron

=

= 7 x 10¹⁰

Electric field at 13 cm

=

E= 375 N/C

what was the answer?

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.