Question

A dust particle has an excess charge of 3.0× 10 6 electrons and a mass of 9.0× 10 −8 g . It is initially held at d=1.0× 10 −3 m directly above a fixed object of the same size that is charged with the same number of electrons. Both objects are in an evacuated container.

Determine the maximum height of the dust particle after its release measured from its initial position.

What quantities can be determined using the given data?

Check all that apply.

the forces exerted on the dust particle by the stationary charge

the mass of the fixed object

the acceleration of the dust particle

the size of the dust particle

Answer 1

At maximum height speed of dust particle is zero, that is it's kinetic energy is equal to initial kinetic energy. So change in total potential energy is also zero. Hence st maximum height,

Decrease in electrical potential energy = Increase in gravitational potential energy.

DUST PARrLLE 产> 0 4.8X10-13 2

From given data, we can find force on dust particle and it's acceleration.