physics

When capacitors are connected in series, their equivalent capacitance:  

• Increases 

• Decreases 

• Remains the same 

• Depends on voltage

The magnetic field inside a long solenoid is:   

• Uniform 

• Zero

• Non-uniform 

• Circular

The force between two parallel current-carrying wires depends on their: 

• Lengths 

• Current directions

• Resistances 

• Both A and B 

 What is the SI unit of electric charge?  

• Ohm 

• Volt 

• Coulomb 

• Ampere

A circuit with a 12 V battery, two resistors (3 Ω and 6 Ω) in parallel, and an ammeter in series with the battery.  What is the reading on the ammeter?   

• 2 A 

• 4 A 

• 6 A 

• 12 A 

A closed loop with three resistors (2 Ω, 4 Ω, 6 Ω) in series and a 24 V battery.  What is the voltage drop across the 4 Ω resistor?   

• 4 V 

• 8 V 

• 12 V

• 24 V 

A bar magnet with labeled poles (N and S) and field lines.  Which statement is true?  

• Field lines are densest near the poles. 

• Field lines exit the South pole. 

• Field lines cross each other. 

• Field lines are straight. 

A straight vertical wire with current flowing downward.  What is the direction of the magnetic field at a point directly east of the wire?

  

• Into the page 

• Out of the page

• Clockwise

• Counterclockwise

Two parallel wires carry current in the same direction.  How do the wires interact?  

• Twist into a helix 

• No force 

• Repel each other 

• Attract each other

A step-up transformer with 100 turns in the primary coil and 500 turns in the secondary.  If the input voltage is 50 V AC, what is the output voltage?   

• 10 V 

• 250 V

• 500 V 

• 1000V