Question 1

A certain transformer doubles input voltage.If the primary coil has 10 A of current,then the current in the secondary coil is

Accepted Answer

A) 2 A. 
B) 5 A. 
C) 10 A. 
D) 25 A. 
E) none of the above 
A) 2 A. 
B) 5 A. 
C) 10 A. 
D) 25 A. 
E) none of the above

Question 2

The magnetic field lines generated by a bar magnet

Accepted Answer

A) are external only. 
B) are both external and internal to the magnet. 
C) follow an inverse-square law. 
D) none of the above 
A) are external only. 
B) are both external and internal to the magnet. 
C) follow an inverse-square law. 
D) none of the above

Question 3

A transformer has an input of 6 V and an output of 42 V.If the input is changed to 12 V,the output would be

Accepted Answer

A) 12 V. 
B) 48 V. 
C) 84 V. 
D) more than 84 V. 
E) none of the above 
A) 12 V. 
B) 48 V. 
C) 84 V. 
D) more than 84 V. 
E) none of the above

Question 4

Near our planet Earth are

Accepted Answer

A) cosmic rays. 
B) magnetic fields. 
C) both of these 
D) none of the above 
A) cosmic rays. 
B) magnetic fields. 
C) both of these 
D) none of the above

Question 5

A magnetic field exists in a current-carrying coil of wire

Accepted Answer

A) if it contains a piece of iron. 
B) with or without a contained piece of iron. 
C) only if the current changes. 
A) if it contains a piece of iron. 
B) with or without a contained piece of iron. 
C) only if the current changes.

Question 6

An electric motor and electric generator are

Accepted Answer

A) very similar devices. 
B) entirely different devices. 
C) none of the above 
A) very similar devices. 
B) entirely different devices. 
C) none of the above

Question 7

When a bar magnet is thrust into a coil of wire,the coil

Accepted Answer

A) attracts the magnet as it enters. 
B) repels the magnet as it enters. 
C) both of these 
D) none of the above 
A) attracts the magnet as it enters. 
B) repels the magnet as it enters. 
C) both of these 
D) none of the above

Question 8

When a bar magnet is broken in half,the strength of the four new poles relative to pole strength before breaking is

Accepted Answer

A) less than half. 
B) half. 
C) the same. 
D) somewhat more. 
A) less than half. 
B) half. 
C) the same. 
D) somewhat more.

Question 9

Voltage can be induced in a wire by

Accepted Answer

A) moving the wire near a magnet. 
B) moving a magnet near the wire. 
C) changing the current in a nearby wire. 
D) all of the above 
E) none of the above 
A) moving the wire near a magnet. 
B) moving a magnet near the wire. 
C) changing the current in a nearby wire. 
D) all of the above 
E) none of the above

Question 10

No magnetic force acts on a current carrying wire when it

Accepted Answer

A) carries a very small current. 
B) is perpendicular to the magnetic field. 
C) either or both of these 
D) none of the above 
A) carries a very small current. 
B) is perpendicular to the magnetic field. 
C) either or both of these 
D) none of the above

Question 11

If you drop a bar magnet in a vertical copper pipe it will fall slowly because

Accepted Answer

A) of air resistance. 
B) it induces a magnetic field in the pipe that resists motion of the magnet. 
C) the copper is a good conductor of both electricity and magnetism. 
D) of electron repulsion. 
A) of air resistance. 
B) it induces a magnetic field in the pipe that resists motion of the magnet. 
C) the copper is a good conductor of both electricity and magnetism. 
D) of electron repulsion.

Question 12

A device that transforms mechanical energy to electrical energy is a

Accepted Answer

A) generator. 
B) motor. 
C) transformer. 
D) magnet. 
E) none of the above 
A) generator. 
B) motor. 
C) transformer. 
D) magnet. 
E) none of the above

Question 13

Faraday's law describes

Accepted Answer

A) electromagnetic induction. 
B) the connection between current,voltage,and resistance. 
C) the attraction and repulsion of magnetic poles. 
D) the force between magnetic poles. 
E) all of the above 
A) electromagnetic induction. 
B) the connection between current,voltage,and resistance. 
C) the attraction and repulsion of magnetic poles. 
D) the force between magnetic poles. 
E) all of the above

Question 14

If the primary of a transformer were connected to a dc power source,the transformer would have a voltage output

Accepted Answer

A) at a higher efficiency than with an ac source. 
B) the same as its input. 
C) that is also dc. 
D) only briefly while being connected or disconnected. 
E) none of the above 
A) at a higher efficiency than with an ac source. 
B) the same as its input. 
C) that is also dc. 
D) only briefly while being connected or disconnected. 
E) none of the above

Question 15

An electron beam directed through a magnetic field

Accepted Answer

A) may be deflected. 
B) may experience a force. 
C) both of these 
D) neither of these 
A) may be deflected. 
B) may experience a force. 
C) both of these 
D) neither of these

Question 16

Induced electric and magnetic fields produce

Accepted Answer

A) stronger electric or magnetic field. 
B) higher voltages produced by Faraday induction. 
C) both of these 
D) none of the above 
A) stronger electric or magnetic field. 
B) higher voltages produced by Faraday induction. 
C) both of these 
D) none of the above

Question 17

Alternating current is normally produced by a

Accepted Answer

A) battery. 
B) generator. 
C) both of these 
D) none of the above 
A) battery. 
B) generator. 
C) both of these 
D) none of the above

Question 18

Magnet A has twice the magnetic field strength of magnet B and pulls on magnet B with a force of 100 N.The amount of force that magnet A exerts on magnet B is

Accepted Answer

A) about 50 N. 
B) exactly 100 N. 
C) more than 100 N. 
D) not enough information 
A) about 50 N. 
B) exactly 100 N. 
C) more than 100 N. 
D) not enough information

Question 19

What happens to a current-carrying wire in a magnetic field? How does orientation of the wire make a difference?

Accepted Answer

A current-carrying wire properly oriente

Question 20

The minimum or no magnetic force on a moving electron occurs for motion

Accepted Answer

A) parallel to the magnetic field. 
B) perpendicular to the magnetic field. 
C) at non-right angles to the magnetic field direction. 
A) parallel to the magnetic field. 
B) perpendicular to the magnetic field. 
C) at non-right angles to the magnetic field direction.

Exam 9: Magnetism and Electromagnetic Induction

A certain transformer doubles input voltage.If the primary coil has 10 A of current,then the current in the secondary coil is

The magnetic field lines generated by a bar magnet

A transformer has an input of 6 V and an output of 42 V.If the input is changed to 12 V,the output would be

Near our planet Earth are

A magnetic field exists in a current-carrying coil of wire

An electric motor and electric generator are

When a bar magnet is thrust into a coil of wire,the coil

When a bar magnet is broken in half,the strength of the four new poles relative to pole strength before breaking is

Voltage can be induced in a wire by

No magnetic force acts on a current carrying wire when it

If you drop a bar magnet in a vertical copper pipe it will fall slowly because

A device that transforms mechanical energy to electrical energy is a

Faraday's law describes

If the primary of a transformer were connected to a dc power source,the transformer would have a voltage output

An electron beam directed through a magnetic field

Induced electric and magnetic fields produce

Alternating current is normally produced by a

Magnet A has twice the magnetic field strength of magnet B and pulls on magnet B with a force of 100 N.The amount of force that magnet A exerts on magnet B is

What happens to a current-carrying wire in a magnetic field? How does orientation of the wire make a difference?

The minimum or no magnetic force on a moving electron occurs for motion

Patterns of Motion and Equilibrium

Newtons Laws of Motion

Momentum and Energy

Gravity, Projectiles, and Satellites

Fluid Mechanics

Thermal Energy and Thermodynamics

Heat Transfer and Change of Phase

Static and Current Electricity

Waves and Sound

Light

Atoms and the Periodic Table

The Atomic Nucleus and Radioactivity

Elements of Chemistry

How Atoms Bond and Molecules Attract

Mixtures

How Chemicals React

Two Classes of Chemical Reactions

Organic Compounds

Rocks and Minerals

Plate Tectonics and Earths Interior

Shaping Earths Surface

Geologic Time - Reading the Rock Record

The Oceans, Atmosphere, and Climatic Effects

Driving Forces of Weather

The Solar System

Stars and Galaxies

The Structure of Space and Time

Prologue: The Nature of Science

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