Understanding the Motor Effect

What happens to the wire when the current direction is altered?

• It remains stationary

• It heats up without moving

• It swings in the opposite direction

• It vibrates without changing direction

Answer explanation

When the current direction is altered, the wire experiences a force due to the magnetic field, causing it to swing in the opposite direction.

What is necessary for a current-bearing wire to experience a force in a magnetic field?

• The wire must be coated with a magnetic material

• The wire must be perpendicular to the magnetic field

• The wire must be insulated

• The wire must be parallel to the magnetic field

Answer explanation

The wire must be perpendicular to the magnetic field in order to experience a force.

What are the variables that affect the strength of the force on the wire?

• Voltage, current, and temperature of the wire

• Magnetic field, current, and length of the wire

• Magnetic field, voltage, and length of the wire

• Magnetic field, current, and color of the wire

Answer explanation

The variables that affect the strength of the force on the wire are magnetic field, current, and length of the wire.

What does the formula F = BIL sin(theta) represent?

• The force on a wire due to gravity

• The force on a current-bearing wire in a magnetic field

• The resistance of a wire in a magnetic field

• The potential energy of a wire in a magnetic field

Answer explanation

The formula F = BIL sin(theta) represents the force on a current-bearing wire in a magnetic field.

What role does the angle (theta) play in determining the force on the wire?

• The angle determines the color of the wire

• The angle affects the component of the force perpendicular to the magnetic field

• The angle has no effect on the force

• The angle determines the resistance of the wire

Answer explanation

The angle affects the component of the force perpendicular to the magnetic field

How does changing the direction of the current affect the direction of the force?

• The force doubles in magnitude

• The force direction remains unchanged

• The force direction is reversed

• The force becomes zero

Answer explanation

Changing the direction of the current results in the force direction being reversed.

What is the motor effect?

• The rotational effect of a wire around a magnet

• The force experienced by a current-bearing wire in a magnetic field

• The magnetic effect of current on a wire

• The heating effect of current on a wire

Answer explanation

The motor effect refers to the force experienced by a current-bearing wire in a magnetic field, making it the correct choice.

Which hand rule is used to determine the direction of the force?

• Neither left-hand nor right-hand rule

• Both left-hand and right-hand rules can be used

• Right-hand rule

• Left-hand rule

Answer explanation

Both left-hand and right-hand rules can be used to determine the direction of the force in physics.

What does the term 'L sine theta' represent in the context of the force on a wire?

• The vertical component of the length of wire

• The total length of the wire

• The horizontal component of the length of wire

• The resistance of the wire

Answer explanation

The term 'L sine theta' represents the vertical component of the length of wire in the context of the force on a wire.

How can the direction of the magnetic field be determined?

• By measuring the wire's resistance

• Using the right-hand or left-hand rule based on the direction of current and force

• By measuring the temperature of the wire

• By changing the current's direction

Answer explanation

The direction of the magnetic field can be determined using the right-hand or left-hand rule based on the direction of current and force.