1

Atoms found in the atmosphere of our star like our sun are often ionized due to interactions between the electric and magnetic fields of the sun and the other atoms and molecules present.  What is the net charge of an iron atom, which has 26 protons in its nucleus, 30 neutrons, and has 19 electrons in orbit about the nucleus?

 

A.

C.

 

 

 

 

B.

D.

 

 

Neutrons have no net charge.  Since there are 26 protons and 19 electrons, there are 7 more protons than electrons.  So positive net charge and the 7 times charge of a proton/electron.

 

So Correct Answer is B !

2

An object has a net charge of  is placed in an electric field which can be described by .  What is the electric force that acts on the object?

 

A.

C.

 

 

 

 

B.

D.

 

 

 

So Correct Answer is A !

3

A charged object is found in space.  When a test charge of  is  away it experiences an electrical force of  causes the test charge to be drawn towards the charged object.  What is the net charge on the object found in space?

 

A.

B.

C.

 

D.

 

 

Solving for the point charge

 

 

- sign resolves the vector directions.  Since the test charge is attracted to object, the object must be oppositely signed so negative.

 

 

 

So Correct Answer is D !

4

Two identical metal spheres (A and B) initially have charges  and .  They are brought together and touch for 5 minutes.  Then they are separated, what is the final charge on sphere B?

 

A.

B.

C.

 

D.

 

 

When they touch since they are identical spheres the charges redistribute and when separated each will have half the total charge that resulted from their joining.

 

 

So the Correct Answer is C !

 

 

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This page last updated on September 18, 2020