PHY101 Most Important MCQs/Midterm Solved Past Paper

 

Question No: 1 ( Marks: 1 ) 

The SI standard of time is based on:

A. the daily rotation of the earth

B. the frequency of light emitted by Kr86

C. the yearly revolution of the earth about the sun

D. a precision pendulum clock

E. none of these

Question No: 2 ( Marks: 1 ) - 

A net torque applied to a rigid object always tends to produce:

► rotational equilibrium

► linear acceleration

► angular acceleration

► rotational inertia

Question No: 3 ( Marks: 1 ) -

An object attached to one end of a spring makes 20 vibrations in 10 s. Its

angular frequency is:

► 12.6 rad/s

► 1.57 rad/s

► 2.0 rad/s

► 6.3 rad/s

Question No: 4 ( Marks: 1 ) - 

In simple harmonic motion, the restoring force must be proportional to the:

► amplitude

► frequency

► velocity

► displacement

Question No: 5 ( Marks: 1 ) - 

Mercury is a convenient liquid to use in a barometer because:

► it is a metal

► it has a high boiling point

► it expands little with temperature

► it has a high density

Question No: 6 ( Marks: 1 ) - 

The units of the electric field are:

► J/m

► J/(C·m)

► J/C

► J·C

Question No: 7 ( Marks: 1 ) - 

A farad is the same as a

► J/V

► V/J

► C/V

► V/C

Question No: 8 ( Marks: 1 ) - 

We desire to make an LC circuit that oscillates at 100 Hz using an

inductance of 2.5H. We also need a capacitance of:

► 1 F

► 1mF

► 1 μF

► 100 μF

Question No: 9 ( Marks: 1 ) - 

The wavelength of red light is 700 nm. Its frequency is

____________________.

► 4.30 * 104 Hertz

► 4.30 * 103 Hertz

► 4.30 * 105 Hertz

► 4.30 * 102 Hertz

Question No: 10 ( Marks: 1 ) -Which of the following statements isNOT TRUE about electromagnetic

waves?

► Electromagnetic waves satisfy the Maswell's Equation.

► Electromagnetic waves can not travel through space.

► The receptions of electromagnetic waves require an antenna.

► The electromagnetic radiation from a burning candle is

unpolarized.

Question No: 11 ( Marks: 1 ) -

Radio waves and light waves are ____________________________.

► Longitudinal waves

► Transverse waves

► Electromagnetic and transverse both

► Electromagnetic and longitudinal both

Question No: 12 ( Marks: 1 ) -

Wien's Law states that, lmax = ________ K.

► 2.90 * 10-3 Hertz

► 2.90 * 10-3 s

► 2.90 * 10-3 kg

► 2.90 * 10-3 m

Question No: 13 ( Marks: 1 ) -

Interference of light is evidence that:

► the speed of light is very large

► light is a transverse wave

► light is a wave phenomenon

► light is electromagnetic in character

Question No: 14 ( Marks: 1 ) - 

Fahrenheit and Kelvin scales agree numerically at a reading of:

► -40

► 0

► 273

► 574

Question No: 15 ( Marks: 1 ) - 

According to the theory of relativity:

► moving clocks run fast

► energy is not conserved in high speed collisions

► the speed of light must be measured relative to the ether

► none of the above are true

Question No: 16 ( Marks: 1 ) - 

Light from a stationary spaceship is observed, and then the spaceship moves

directly away from the observer at high speed while still emitting the light.

As a result, the light seen by the observer has:

► higher frequency and a longer wavelength than before

► lower frequency and a shorter wavelength than before

► higher frequency and a shorter wavelength than before

► lower frequency and a longer wavelength than before

Question No: 17 ( Marks: 1 ) - 

How fast should you move away from a 6.0 × 1014 Hz light source to

observe waves with a frequency of 4.0 × 1014 Hz?

► 20c

► 38c

► 45c

► 51c

Question No: 18 ( Marks: 1 ) - The quantum number n is most closely associated with what property of the

electron in a hydrogen atom?

► Energy

► Orbital angular momentum

► Spin angular momentum

► Magnetic moment

Question No: 19 ( Marks: 1 ) - 

The quantum number ms is most closely associated with what property of the

electron in an atom?

► Magnitude of the orbital angular momentum

► Energy

► z component of the spin angular momentum

► z component of the orbital angular momentum

Question No: 20 ( Marks: 1 ) - 

As the wavelength of a wave in a uniform medium increases, its speed will

_____.

► Decrease

► Increase

► Remain the same

► None of these

Question No: 1 ( Marks: 1 ) - The lowest tone produced by a certain organ comes from a 3.0-m pipe with

both ends open. If the speed of sound is 340m/s, the frequency of this tone is

approximately:

► A. 7Hz

► B. 14 Hz

► C. 28 Hz

► D. 57 Hz

Question No: 2 ( Marks: 1 ) - 

1. To raise the pitch of a certain piano string, the piano tuner:

► A. loosens the string

► B. tightens the string

► C. shortens the string

► D. lengthens the string

Question No: 7 ( Marks: 1 ) - 

An object attached to one end of a spring makes 20 vibrations in 10 s. Its

angular frequency is:

► 12.6 rad/s

► 1.57 rad/s

► 2.0 rad/s

► 6.3 rad/s

Question No: 8 ( Marks: 1 ) - For an object in equilibrium the net torque acting on it vanishes onl

y if each

torque is calculated about:

► the center of mass

► the center of gravity

► the geometrical center

► the same point

Question No: 9 ( Marks: 1 ) -

Ten seconds after an electric fan is turned on, the fan rotates at 300 rev/min.

Its average angular acceleration is:

► 3.14 rad/s2

► 30 rad/s2

► 30 rev/s2

► 50 rev/min2

► 1800 rev/s2

Question No: 10 ( Marks: 1 ) - 

A 4.0-N puck is traveling at 3.0m/s. It strikes a 8.0-N puck, which is

stationary. The two pucks stick together. Their common final speed is:

► 1.0m/s

► 1.5m/s

► 2.0m/s

► 2.3m/s

Question No: 11 ( Marks: 1 ) - 

An object moving in a circle at constant speed:

► must have only one force acting on it

► is not accelerating

► is held to its path by centrifugal force

► has an acceleration of constant magnitude

Question No: 12 ( Marks: 1 ) - 

A plane traveling north at 200m/s turns and then travels south at 200m/s.

The change in its velocity is:

► 400m/s north

► 400m/s south

► zero

► 200m/s south

Question No: 13 ( Marks: 1 ) - 

At time t = 0 a car has a velocity of 16 m/s. It slows down with an

acceleration given by −0.50t, in m/s2 for t in seconds. It stops at t =

► 64 s

► 32 s

► 16 s

► 8.0 s

Question No: 14 ( Marks: 1 ) - 

1 mi is equivalent to 1609 m so 55 mph is:

► 15 m/s

► 25 m/s

► 66 m/s

► 88 m/s

The number of significant figures in 0.00150 is:

► 5

► 4

► 3

► 2

Question No: 2 ( M a r k s: 1 )

One revolution is the same as:

2π rad

► 1 rad

► 57 rad

► π/2 rad

► π rad

► 2π rad

Question No: 3 (M a r k s: 1)

For a body to be in equilibrium under the combined action of several forces:

► All the forces must be applied at the same point

all the forces must be applied at the same point

► all of the forces form pairs of equal and opposite forces

► any two of these forces must be balanced by a third force

► the sum of the torques about any point must equal zero

PHY101 - Physics - Question No: 4 ( M a r k s: 1 )

A bucket of water is pushed from left to right with increasing speed across a

horizontal surface.

Consider the pressure at two points at the same level in the water.

► It is the same

► It is higher at the point on the left

► It is higher at the point on the right

► At first it is higher at the point on the left but as the bucket speeds up it

is lower there

PHY101 - Physics - Question No: 5 (M a r k s: 1)

An organ pipe with both ends open is 0.85m long. Assuming that the speed

ofsound is 340m/s, the frequency of the third harmonic of this pipe is:

► A. 200 Hz

► B. 300 Hz

► C. 400 Hz

► D. 600 Hz

Question No: 6 ( M a r k s: 1 )

Capacitors C1 and C2 are connected in series. The equivalent capacitance is

given by

► C1C2/(C1 + C2)

► (C1 + C2)/C1C2

► 1/(C1 + C2)

► C1/C2

PHY101 - Physics - Question No: 7 ( M a r k s: 1 )

If the potential difference across a resistor is doubled:

► only the current is doubled

► only the current is halved

► only the resistance is doubled

► only the resistance is halved

PHY101 - Physics - Question No: 8 ( M a r k s: 1 )

By using only two resistors, R1 and R2, a student is able to obtain

resistances of 3Ω, 4Ω, 12Ω, and 16 Ω. The values of R1 and R2 (in ohms)

are:

► 3, 4

► 2, 12

► 3, 16

► 4, 12

PHY101 - Physics - Question No: 9 ( M a r k s: 1 )

Faraday's law states that an induced emf is proportional to:

► the rate of change of the electric field

► the rate of change of the magnetic flux

► the rate of change of the electric flux

► the rate of change of the magnetic field

PHY101 - Physics - Question No: 10 ( M a r k s: 1 )

A generator supplies 100V to the primary coil of a transformer. The primary

has 50 turns and the secondary has 500 turns. The secondary voltage is:

► 1000V

► 500V

► 250V

► 100V

PHY101 - Physics - Question No: 14 ( M a r k s: 1 )

Which of the following electromagnetic radiations has photons with the

greatest energy?

► blue light

► yellow light

► x rays

► radio waves

PHY101 - Physics - Question No: 15 ( M a r k s: 1 )

A virtual image is one:

► toward which light rays converge but do not pass through

► from which light rays diverge as they pass through

► toward which light rays converge and pass through

► from which light rays diverge but do not pass through

PHY101 - Physics - Question No: 16 ( M a r k s: 1 ) vuzs

What is the unit of magnification factor?

► meter.Kelvin

► radian.Kelvin

► degree.Kelvin

► no units

Question No: 17 ( M a r k s: 1 )

During an adiabatic process an object does 100 J of work and its temperature

decreases by 5K. During another process it does 25 J of work and its

temperature decreases by 5 K. Its heat capacity for the second process is.

► 20 J/K

► 100 J/K

► 15 J/K

► 5 J/K

Question No: 18 ( M a r k s: 1 )

An ideal gas expands into a vacuum in a rigid vessel. As a result there is:

► a change in entropy

► a decrease of internal energy

► an increase of pressure

► a change in temperature

Question No: 19 ( M a r k s: 1 )

The Stern-Gerlach experiment makes use of:

► a strong uniform magnetic field

► a strong non-uniform magnetic field

► a strong uniform electric field

► a strong non-uniform electric field

Question No: 20 ( M a r k s: 1 )

A large collection of nuclei are undergoing alpha decay. The rate of decay at

any

instant is proportional to:

► the number of undecayed nuclei present at that instant

► the time since the decays started

► the time remaining before all have decayed

► the half-life of the decay

Question No: 1 ( Marks: 1 ) - Vustudentnings.blogspot.com

As a 2.0-kg block travels around a 0.50-m radius circle it has an angular

speed of 12 rad/s. The circle is parallel to the xy plane and is centered on the

z axis, a distance of 0.75m from the origin. The z component of the angular

momentum around the origin is:

► 6.0kg · m2/s

► 9.0kg · m2/s

► 11 kg · m2/s

► 14 kg · m2/s