PhysX #2

Question 1 of 30

1

Which of the following is not generally observed in a geomagnetic storm?

Select one of the following:

Charged particles streaming out from the Sun
Fluctuations in the Earth’s magnetic field
Disruption of electrical power transmission
Disruption of microwave propagation

Explanation

Question 2 of 30

1

A device that reverses magnetic field polarity to keep a dc motor rotating is

Select one of the following:

A solenoid
An armature coil
A commutator
A field coil

Explanation

Question 3 of 30

1

When the speed at which a conductor is moved through a magnetic field is increased, the induced voltage

Select one of the following:

Increases
Decreases
Remains constant
Reaches zero

Explanation

Question 4 of 30

1

For a given wirewound core, an increase in current through the coil

Select one of the following:

Reverses the flux lines
Decreases the flux density
Increases the flux density
Causes no change in flux density

Explanation

Question 5 of 30

1

Which statements are correct?

Select one of the following:

Charges of opposite sign attract one another and charges of the same sign repel one another. Total charge in an isolated system is conserved. Charge is quantized.
Charges of opposite sign repel one another and charges of the same sign attract one another. Total charge in an isolated system is conserved. Charge is quantized.
Charges of opposite sign attract one another and charges of the same sign repel one another. Total charge in an isolated system is not conserved. Charge is quantized.
Charges of opposite sign repel one another and charges of the same sign attract one another. Total charge in an isolated system is ot conserved. Charge is not quantized.
No correct answer

Explanation

Question 6 of 30

1

When a box rests on the floor, it is acted upon by the gravitational and the _________________ force.

Select one of the following:

Centrifugal
Acceleration
Normal
Inertia
Friction

Explanation

Question 7 of 30

1

Motion is produced by

Select one of the following:

All forces
Unbalanced forces
Balanced forces
The absence of force
None of them

Explanation

Question 8 of 30

1

In inelastic collision between the two bodies __________.

Select one of the following:

Only momentum of the system is conserved
Only the kinetic Energy of the system is conserved
Both the kinetic Energy and Momentum of the system remain the same
Total energy is not conserved

Explanation

Question 9 of 30

1

In elastic collision between the two bodies __________.

Select one of the following:

Only momentum of the system is conserved
Only the kinetic Energy of the system is conserved
Both the kinetic Energy and Momentum of the system remain the same
Total energy is not conserved

Explanation

Question 10 of 30

1

When the force and displacement are parallel to each other, then work is __________.

Select one of the following:

Minimum
Maximum
None of these
Depends on force magnitude

Explanation

Question 11 of 30

1

In rotational motion, the quantity, which plays the same role as the inertial mass in linear motion, is called ___________.

Select one of the following:

Inertia
Angular momentum
Moment of inertia
Torque
Center of mass

Explanation

Question 12 of 30

1

A sound wave can be characterized as

Select one of the following:

A transverse wave
A longitudinal wave
A transverse wave or a longitudinal wave, depending on the nature of its source
One that carries no energy
A wave that does not require a medium to be transmitted from one place to the other

Explanation

Question 13 of 30

1

A woman sits on a spinning stool with her arms folded. When she extends her arms, which of the following occurs

Select one of the following:

She increases her moment of inertia, thus increasing her angular speed
She increases her moment of inertia, thus decreasing her angular speed.
She decreases her moment of inertia, thus increasing her angular speed
She decreases her moment of inertia, thus decreasing her angular speed
Her angular speed remains constant by conservation of angular momentum

Explanation

Question 14 of 30

1

The ability of a material to remain magnetized after removal of the magnetizing force is known as

Select one of the following:

Permeability
Reluctance
Hysteresis
Retentivity

Explanation

Question 15 of 30

1

The induced voltage across a stationary conductor in a stationary magnetic field is

Select one of the following:

Zero
Reversed in polarity
Increased
Decreased

Explanation

Question 16 of 30

1

When a solenoid is activated, the force that moves the plunger is

Select one of the following:

An electromagnetic field
A permanent magnetic field
Varying voltage
A steady current

Explanation

Question 17 of 30

1

If a loop in a basic dc generator suddenly begins rotating at a faster speed, the induced voltage

Select one of the following:

Remains unchanged
Reverses polarity
Increases
Decreases

Explanation

Question 18 of 30

1

You charge parallel-plate capacitor. When you pull the plates apart to a larger separation and battery remains connected to the capacitor

Select one of the following:

Decreases
Remains the same
Alternates
Increases
Changes in an unpredictable way

Explanation

Question 19 of 30

1

Induction current opposes the reason causing it. It is the shortest formulation of

Select one of the following:

Einstein’s law
Lentz law
Biot-Savart law
Faraday’s law
Ampere’s law

Explanation

Question 20 of 30

1

Paramagnetism is closely associated with

Select one of the following:

The torque
The force exerted by electron dipole moments on each other
The tendency of electron dipole moments to align with an applied magnetic field
The exchange force between electrons
The tendency of electrons dipole moments to align opposite to an applied magnetic field

Explanation

Question 21 of 30

1

The thermal conductivity is the analog to:

Select one of the following:

Thermal expansion
Resistivity
Elasticity
Diffusivity
Viscosity

Explanation

Question 22 of 30

1

Resistance of metals in classical theory of electric conductivity is caused by

Select one of the following:

Collision of free electrons with dislocations or clasters
Collision of free electrons with impurity atoms in internodes
Collision of free electrons with each other
Collision of free electrons with vacancy defects
Collision of free electrons with ions of crystal structure

Explanation

Question 23 of 30

1

Electric theory of dispersion was evaluated by:

Select one of the following:

Lorentz
Newton
Einstein
Minkovsky
Maxwell

Explanation

Question 24 of 30

1

Loop is uniformly rotating with angular velocity ω in uniform magnetic field. Loop has N coils and area of the loop is S. Rotating axis lies on loop’s plane and perpendicular to induction. What is the maximal EMF appeared in the loop:

Select one of the following:

NBS/2
NBS
NBScos(wt)
NBSw/2
NBSw

Explanation

Question 25 of 30

1

An electrton traveling with speed v around a circle of radius r is equivalent to a current of:

Select one of the following:

evr/2
ev/r
2πer/v
2πev/r
ev/2πr

Explanation

Question 26 of 30

1

An electromagnetic field propagates in +x direction. The electric field at a point in space is momentarily oriented in –z
direction. The magnetic field at that point is momentarily oriented in

Select one of the following:

–y direction
+y direction
+z direction
+x direction
-x direction

Explanation

Question 27 of 30

1

In RLC circuit angular frequency of AC source rises. Inductive reactance

Select one of the following:

Remains the same
Increases
Oscillates about certain value
Alternates
Decreases

Explanation

Question 28 of 30

1

The rapid exponential decay in just a few cycles of the charge on the plates of capacitor in an RLC circuit might be due to:

Select one of the following:

A large capacitance
A small capacitance
A large resistance
A small resistance
A large inductance

Explanation

Question 29 of 30

1

Intrinsic semiconductors are

Select one of the following:

Materials doped by impurities
Pure elemental materials without impurities
Materials doped by donor impurity
Materials doped by acceptor impurity
Any materials

Explanation

Question 30 of 30

1

In a charge-free region of space, closed container is placed in an electric field. A requirement for the total electric flux through the surface of the container to be zero is that

Select one of the following:

The field must be uniform
The container must be oriented in a certain way
The container must be symmetric
The requirement does not exist – the total electric flux is zero no matter what

	Created by Hanzo Conard almost 8 years ago

just quiz

Question 1 of 30

Which of the following is not generally observed in a geomagnetic storm?

Select one of the following:

Explanation

Question 2 of 30

A device that reverses magnetic field polarity to keep a dc motor rotating is

Select one of the following:

Explanation

Question 3 of 30

When the speed at which a conductor is moved through a magnetic field is increased, the induced voltage

Select one of the following:

Explanation

Question 4 of 30

For a given wirewound core, an increase in current through the coil

Select one of the following:

Explanation

Question 5 of 30

Which statements are correct?

Select one of the following:

Explanation

Question 6 of 30

When a box rests on the floor, it is acted upon by the gravitational and the _________________ force.

Select one of the following:

Explanation

Question 7 of 30

Motion is produced by

Select one of the following:

Explanation

Question 8 of 30

In inelastic collision between the two bodies __________.

Select one of the following:

Explanation

Question 9 of 30

In elastic collision between the two bodies __________.

Select one of the following:

Explanation

Question 10 of 30

When the force and displacement are parallel to each other, then work is __________.

Select one of the following:

Explanation

Question 11 of 30

In rotational motion, the quantity, which plays the same role as the inertial mass in linear motion, is called ___________.

Select one of the following:

Explanation

Question 12 of 30

A sound wave can be characterized as

Select one of the following:

Explanation

Question 13 of 30

A woman sits on a spinning stool with her arms folded. When she extends her arms, which of the following occurs

Select one of the following:

Explanation

Question 14 of 30

The ability of a material to remain magnetized after removal of the magnetizing force is known as

Select one of the following:

Explanation

Question 15 of 30

The induced voltage across a stationary conductor in a stationary magnetic field is

Select one of the following:

Explanation

Question 16 of 30

When a solenoid is activated, the force that moves the plunger is

Select one of the following:

Explanation

Question 17 of 30

If a loop in a basic dc generator suddenly begins rotating at a faster speed, the induced voltage

Select one of the following:

Explanation

Question 18 of 30

You charge parallel-plate capacitor. When you pull the plates apart to a larger separation and battery remains connected to the capacitor

Select one of the following:

Explanation

Question 19 of 30

Induction current opposes the reason causing it. It is the shortest formulation of

Select one of the following:

Explanation

Question 20 of 30

Paramagnetism is closely associated with

An electromagnetic field propagates in +x direction. The electric field at a point in space is momentarily oriented in –z
direction. The magnetic field at that point is momentarily oriented in