Electromagnetic Induction

What is the main difference between electric charges and magnetic poles?

• electric charges can be isolated, magnetic poles cannot be isolated

• electric charges cannot be isolated, magnetic poles can be isolated

• electric charges both attract and repel, magnetic poles only attract

• electric charges both attract and repel, magnetic poles only repel

A bar magnet is brought into a loop of wire at a constant speed. At the moment shown in the figure,

• The induced current alternates back and forth.

• The induced current is at a constant amperage.

• The induced current is increasing.

• The induced current is decreasing.

The current within a straight conducting wire is increasing at a constant rate. The magnetic field around the wire is...

• alternating back and forth

• remaining constant

• increasing in magnitude

• decreasing in magnitude

A galvanometer is used to detect minute currents. If the copper rod is raised upwards,

• there is no induced current in the rod

• the current flows to the left in the rod

• the current flows to the right in the rod

• the copper rod explodes

A transformer has 1000 turns in the primary winding and 100 turns in the secondary winding. The primary voltage is 2,400 V and the primary current is 0.20 A.

• Secondary Voltage: 24,000 V; Secondary Current: 0.020 A

• Secondary Voltage: 240 V; Secondary Current: 0.20 A

• Secondary Voltage: 240 V; Secondary Current: 2.0 A

• Secondary Voltage: 2,300 V; Secondary Current: 0.20 A

A transformer has 1000 turns in the primary winding and 100 turns in the secondary winding. The primary voltage is 2,400 V and the primary current is 0.20 A.

• This is a Step-Up Transformer

• This is a Step-Down Transformer

• This is a two-stepping Transformer

• optimusprimedancing.gif

A transformer has 1000 turns in the primary winding and 100 turns in the secondary winding. This transformer is most likely used to delivery electricity ____

• from a power generator to distribution lines

• from distribution lines for residential use

A magnetic field is directed towards the right. A mass of charge +q is moving with velocity v. What is the magnitude of the magnetic force on the mass?

• qvB into the page

• qvB out of the page

• qvB*sin(30) into the page

• qvB*sin(30) out of the page

A magnetic field is directed out of the screen. A mass of charge +q is moving with velocity v. What is the magnitude of the magnetic force on the mass?

• qvB northwest

• qvB southeast

• qvB*sin(45) northwest

• qvB*sin(45) southeast

A coil of wire moves in (as shown above) and then out of a magnetic field. The direction of the induced current in the wire is...

• first CW then CCW

• first CCW then CW

• first CW then CW

• first CCW then CCW