5

Two charged masses are a distance  apart when they are released from rest. Object 1 has a charge , a mass of and it experiences an acceleration , which is directed away from object 2.  Object 2 has a charge  and an acceleration , which is directed away from object 1..  What is the mass of object 2?

 

A.

C.

 

 

 

 

B.

D.

 

The Electric force between the two charges is found from

 

So all we need is

 

Minus sign is directional so we can drop it and solve for

 

 

 

So Correct answer is A !

6

A cult leader is trying to impress his followers and floating above the ground. She accomplished this by standing on a charged plate and arranging an electric field to be present.  Assume the leader and the plate has a combined mass , and the plate has a charge .  What is the magnitude and direction of the electric field required for this stunt to occur?

 

A.

C.

 

 

 

 

B.

D.

 

Since gravity pulls down, the electric force must push up.  Since the charge is negative, the electric field must point down so that the electric force acts up.

 

 

 

And again it must point down to create force up

 

So Correct Answer is C !

7

An electric field is direct to the right as shown on the right.  The strength of the electric field is .  The field crosses into a cross sectional area  which is angled by an angle .  What is the amount of electric flux passing through the area?

 

A.

C.

 

 

 

 

B.

D.

 

 

 

 

So Correct Answer is D !

8

An electron is moved from the ground to a cloud.  In doing so, the electron lost electrical potential energy in the amount of .  What is the difference in electrical potential between the ground and the cloud?  Also, which is the higher potential Cloud or Ground?

 

A.

, Cloud

C.

, Ground

 

 

 

 

B.

, Ground

D.

, Cloud

 

Solving for

 

 

Since electron is negatively charged, it loses potential energy going from a – potential to a + potential, so the Cloud should be the higher potential.

 

So Correct Answer is A !

 

 

 

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This page last updated on September 18, 2020