A 5 watt LED bulb converts 80% of the power into light photons wavelength 660 nm. What is the number of photons emitted from the bulb in one second.

UHS 2018
Physics
Dawn of Modern Physics
Elimination Tool:

Work done, due to centripetal force, for circular motion will be:

NUMS Mock 1
Physics
Circular Motion and Momentum

4.5 x 109 years is the half-life of:

NUMS 2020
Physics
Nuclear Physics
Elimination Tool:

Spectral lines is like a __________ of absorbed or emission energy in a spectrum.

PMC Sample 3
Physics
Atomic Spectra
Elimination Tool:

The deviation of I-V graph from straight line is due to:

NUMS 2016
Physics
Current Electricity
Elimination Tool:

A square coil of 16 cm has 200 turns and rotates in a uniform magnetic field of magnitude 0.05 T. If the peak emf is 12 V, what is the angular velocity of the coil?

NUMS 2015
Physics
Circular Motion and Momentum
Elimination Tool:

Parsec(pc) is the unit of ?

ECG records

Dimensions of torsional couple Is similar to the dimension of

The ratio of mass of electron to neutron is:

PMC Practice 4
Physics
Atomic Spectra
Elimination Tool:

Compression of gas under constant temperature is process:

Laser beam can be used to generate three dimensional objects in a process called:

NUMS Mock 1
Physics
Optics, Nature of Light and Optical Instruments

A very large star of mass M and radius r undergoes a transformation into a neutron star. Assume that the mass remains constant while the radius of the star becomes 1/1,000 its original size, (1 × 10−3)r. How does the change in the radius of the star affect the force of gravity, Fg, acting between the star and a planet that is orbiting the star?

NUMS 2014
Physics
Gravitation
Elimination Tool:

Dimensions of U are

If mass attached to a spring and the spring constant of a spring are doubled, the resulting Time period will:

Minimum energy required to eject an electron from metal surface is called:

UHS 2019
Physics
Dawn of Modern Physics
Elimination Tool:

A pendulum is placed at Lahore, Murree, and K2. At which location will the frequency of Pendulum be maximum?

A body Is dropped from a height 175m, how much time will it take to reach the ground?

Which of the following are component of half wave rectifier?

PMC Practice 1
Physics
Alternating Current
Elimination Tool:

A handball is tossed vertically upward with a velocity of 19.6 m/s. Approximately how high will it rise?

NTS 2016 DUHS & JSMU
Physics
Circular Motion and Momentum
Elimination Tool:

If the current in the wire is directed into the page, and the wire is held perpendicular to the page, then the direction of magnetic circles will be:

A car is travelling in a straight line along a highway at a constant speed of 80miles per hour for 10 seconds. Find its acceleration.

NTS 2015 SMBBMC
Physics
Forces and Motion
Elimination Tool:

The frequency of a string on a musical instrument can be changed either by:

PMC Sample 3
Physics
Oscillations and Simple Harmonic Motion
Elimination Tool:

The instrument(s) which work on the principle of Wheatstone bridge is/are:

NTS 2012
Physics
Current Electricity
Elimination Tool:

In a double slit experiment, two slits are 0.2 mm apart with a screen at a distance of 1m. The third bright fringe is found to be displaced at a distance of 7.5 mm from the central fringe. What is the value of the wavelength?

NUMS 2019 Cancelled
Physics
Optics, Nature of Light and Optical Instruments
Elimination Tool:

Mass of a body with speed of light approaches to:

An electron is situated midway between two parallel plates 0.5 cm apart. One of the plates is maintained at a potential of 60 volts above the other. The force on the electron is (e = -1.6×10-19)

NTS 2011
Physics
Electrostatics
Elimination Tool:

When transistor Is forward biased then resistance will be: b a) Nano ohms ) Kilo ohms c) Mega ohms

Two vectors of magnitude 10m and 20m have an angle 30° between them. The component of shorter vector parallel to the longer vector will be:

Water is flowing in a streamline motion through a horizontal tube. The pressure at a point in the tube is P where the velocity of now is v. At another point, where the pressure is P/2, the velocity of flow is: (density of water=ρ)

NUMS 2014
Physics
Fluid Dynamics
Elimination Tool:

An electric cell of e.m.f E, is connected across a copper wire of diameter d and length L. The drift velocity of electrons in the wire is v0. If the length of the wire is changed to 2L, the new drift velocity of electrons in the copper wire will be:

NUMS 2014
Physics
Current Electricity
Elimination Tool:

The ratio of tensile strength to tensile strain is called:

UHS 2012
Physics
Physics of Solids
Elimination Tool:

A proton has mass m and charge q. It is suspended in electric and gravitational field. What is the magnitude of electric field?

PMC Sample 3
Physics
Electrostatics
Elimination Tool:

Displacement is a:

PMC Practice 2
Physics
Scalars and Vectors
Elimination Tool:

When an electron and its antiparticle positron come close enough to each other, they completely convert into radiation energy in the form of photons, this process is called:

NTS 2018
Physics
Dawn of Modern Physics
Elimination Tool:

A particle is travelling along a straight line OX. The distance x (in metre) of the particle from O at a time ′t′ is given by x = 37 +27t – t3 , where ‘t’ is time in seconds. The distance of the particle from O, when it comes to rest is:

NUMS 2014
Physics
Forces and Motion
Elimination Tool:

An object is undergoing simple harmonic motion. It’s time period is T and total energy is E. The amplitude of vibration is reduced to half. What is the new time period and total energy of the system?

PMC Practice 5
Physics
Oscillations and Simple Harmonic Motion
Elimination Tool:

Mechanical energy of an object is the sum of its Potential Energy and ?

least distance of distinct vision

Which is evaporating cooler?

In a certain process, 400 J of heat energy is supplied to a system and at the same time 150 J of work is done by the system. The increase in internal energy of the system is _______.

NUMS 2020
Physics
Heat and Thermodynamics
Elimination Tool:

Consider a peak rectifier fed by a 60-Hz sinusoid having a peak value Vp = 100V. Let the load resistance R = 10kΩ . Calculate the fraction of the cycle during which the diode is conducting:

PMC Practice 5
Physics
Electronics
Elimination Tool:

One wheel has a diameter of 30 inches and a second wheel has a diameter of 20 inches. The first wheel travels a certain distance revolution in 240 revolutions. In how many revolutions did the second wheel travel the same distance.

NUMS 2017
Physics
Circular Motion and Momentum
Elimination Tool:

Find the gravitational force of attraction between two balls each weighing 10 kg, when placed at a distance of 1 meter apart.

NTS 2016 DUHS & JSMU
Physics
Gravitation
Elimination Tool:

Two bodies ‘x’ and ‘Y’ are attached to the ends of a string which passes over a pulley so that the two bodies hang vertically. If the mass of the body ‘x’ is 5 kg and that of body ‘Y’ is 4.8 kg. Find the acceleration?(g = 9.8 m/s^2)

NTS 2015 DUHS and JSMU
Physics
Forces and Motion
Elimination Tool:

Transformer works on the principle of:

NTS 2016 SMBBMC
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

When a charged particle is projected perpendicular to a magnetic field:

NUMS 2016
Physics
Electrostatics
Elimination Tool:

X-rays are used to investigate:

PMC Sample 3
Physics
Dawn of Modern Physics
Elimination Tool:

Electromagnetic wave theory was proposed by:

NTS 2015 SMBBMC
Physics
Dawn of Modern Physics
Elimination Tool:

Moment of inertia in angular motion plays the same role as

On increasing the spring constant to 4 times its value:

Bright Lines in pattern show:

PMC Practice 5
Physics
Atomic Spectra
Elimination Tool:

The number of diodes in centre-tapped full-wave rectifier is:

PMC 2021 Tested
Physics
Electronics
Elimination Tool:

Molecules of a gas at constant pressure for a fixed amount of gas have average kinetic energy X. Increasing temperature from 27˚C to 327˚C, the average K.E. of the molecules will become:

NUMS Mock 4
Physics
Heat and Thermodynamics

The chemical properties of elements depend on ________.

NUMS 2019 Reconduct
Physics
Nuclear Physics
Elimination Tool:

Electrical effects due to friction are studied in:

In a ripple tank, 40 waves pass through a certain point in 1 second. If the wavelength of the wave is 5 cm, then speed of the wave is:

PMC 2020
Physics
Wave Motion and Sound
Elimination Tool:

A nucleus weighs less than Its sum of nucleons, a quantity known as the

What will be the speed a electron having an energy of 18.2 x10^14 Joule?

What will be the energy of electron travelling at 10^7 m/s

Which of the following statements is not true regarding the Newton’s third law of motion?

NUMS 2016
Physics
Forces and Motion
Elimination Tool:

A 100 kg golf ball is moving to the right with a velocity of 20 m/s. It makes a head on collision with an 8 kg steel ball, initially at rest. The two balls get stuck together. What will the velocity of these two balls after collision?

NTS 2015 DUHS and JSMU
Physics
Circular Motion and Momentum
Elimination Tool:

A machine worker placed a cylinder with a diameter of 18 cm between the plates of a hydraulic press. If he applies a 4.25 x 105N force to the cylinder, the stress on the end of the cylinder due to the applied force is A x 107Pa.

What is the value of A?

NUMS 2019 Cancelled
Physics
Heat and Thermodynamics
Elimination Tool:

A Black body is?

The phenomenon in which certain elements emit invisible radiations is called:

NTS 2018
Chemistry
Atomic Spectra
Elimination Tool:

Identify the postulate(s) which help to formulate a mathematical model of gases.

I. A finite volume of gas consists of very large number of molecules

II. The size of the molecules is much smaller than the separation between molecules

III. Molecules do not exert force on each other except during a collision.

NUMS Mock 2
Physics
Heat and Thermodynamics

In SI units, the unit of Candela is used for the measurement of:

NTS 2016 DUHS & JSMU
Physics
Measurements
Elimination Tool:

A 3-cm length of wire is moved at right angles across a uniform magnetic field with a speed of 2.0 m/s . If the flux density is 5.0 teslas, what is the magnitude of the induced e.m.f?

NUMS Mock 1
Physics
Magnetism and Electromagnetic Induction

At least how many diodes are required to covert A.0 fully into D.C?

car travels a distance of 350 miles in 5.0 hours find its average speed.

Which gas is not used in GM counter?

A thin horizontal plate of area 0.036 m2 is beneath the surface of a liquid of density 930 kg m−3. The force on one side of the plate due to the pressure of the liquid is 290 N. What is the depth of the plate beneath the surface of the liquid?

ETEA 2018
Physics
Fluid Dynamics
Elimination Tool:

A particle is projected at an angle of 45 degrees with a velocity of 9.8 m/s. The horizontal range will be:

(g=9.8 m/s2)

NTS 2012
Physics
Motion in Two Dimensions
Elimination Tool:

In transmission from grid station, power losses are minimized by:

PMC 2020
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

A coil is placed near a magnet. Emf will be induced in it when

A bullet on penetrating 30cm into its target loses its velocity by 50%. What additional distance will it penetrate into its target before it comes to rest?

NUMS 2014
Physics
Motion in Two Dimensions
Elimination Tool:

Which of the following is CORRECT for photons?

PMC 2021 Tested
Physics
Electromagnetic Waves
Elimination Tool:

The energy supplied by the cell to the charge carriers is derived from the conversion of:

NUMS Mock 1
Physics
Current Electricity

A half-wave rectifier uses:

PMC Practice 13
Physics
Electronics
Elimination Tool:

A magnetic needle is placed in a uniform magnetic field and is aligned with the field. The needle is now rotated by an angle of 60 degrees and work done is W. The torque on the magnetic needle at this position is

NUMS 2014
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

1 femto

a) 10-15

b) 10-9

c) 10-6

d) None

If a voltage of 9V is applied between ends of a wire whose resistance is 0.2 ohm, what will be the resulting current?

NTS 2015 SMBBMC
Physics
Current Electricity
Elimination Tool:

The unit of impulse is same as of

Fluorescence is produced when cathode rays strike on:

PMC 2021 Tested
Physics
Dawn of Modern Physics
Elimination Tool:

A shot leaves a gun at the rate of 160 m/s. Calculate the greatest distance to which it could be projected. (Take g = 10 m/s2)

NTS 2013
Physics
Motion in Two Dimensions
Elimination Tool:

An electron is moving along the axis of a solenoid carrying a current. Which of the following is a correct statement about the electromagnetic force acting on the electron?

NUMS 2015
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Wave nature of light is proved by:

PMC Practice 1
Physics
Optics, Nature of Light and Optical Instruments
Elimination Tool:

When brakes of a car are applied, angular velocity of a flywheel reduces from 900 cycle / min to 720 cycle / min in 6 sec. Angular retardation is:

NUMS 2015
Physics
Circular Motion and Momentum
Elimination Tool:

If the actual weight of a person standing in an elevator is 75N, and the apparent weight in the accelerated elevator is 105N, find the acceleration and direction of elevator motion. (Use g 10 m/s2)

Escape velocity of moon is

Fusion and fission reactions are associated with:

NTS 2012
Physics
Nuclear Physics
Elimination Tool:

The entropy of the universe always:

NUMS 2016
Physics
Heat and Thermodynamics
Elimination Tool: