TOP 100 Physics MCQS

All Questions for: TOP 100 Physics MCQS

Question 301: The number of significant figures in the length of a bar 6200mm measured by meter rod is_______________?

  • A 4
  • B 2
  • C 3
  • D None of these

Explanation:

Question 302: If Ax is -ve and Ay is +ve, the resultant is:___________?

  • A 4th
  • B 1st
  • C 2nd
  • D 3rd

Explanation:

Question 303: The normal blood pressure range for a human body is______________?

  • A 60 to 140 torr
  • B 120 to 80 torr
  • C 120 to 60 torr
  • D 100 to 80 torr

Explanation:

Question 304: Stopping potential for a metal surface in case of photoelectric emission depends on_____________?

  • A all of the above
  • B the threshold frequency for the metal surface
  • C the frequency of incident light and work function of the metal surface
  • D the intensity of incident light

Explanation:

Question 305: In case of a simple pendulum, the cause of damping is__________________?

  • A None of these
  • B Tension in the string
  • C Gravity
  • D Drag force of air

Explanation:

Question 306: What is the SI unit of modulus of elasticity of substance ?

  • A Nm-2
  • B Being a number it has no unit.
  • C Nm-1
  • D Jm-2

Explanation:

Question 307: Field particle of Electromagnetic interaction is _________?

  • A Vector Boson
  • B Photon
  • C Meson
  • D Graviton

Explanation:

Question 308: The SI unit of Heat is________?

  • A Watt
  • B Volt
  • C Newton
  • D Joule

Explanation:

Question 309: The effect of the decrease in pressure with the increase of the speed of the fluid in a horizontal pipe is known as______________?

  • A Venturi effect
  • B Stokes effect
  • C Bernoulli effect
  • D Torricelli effect

Explanation:

Question 310: A choke is used as a resistance in_________________?

  • A DC circuit
  • B Both AC and DC circuit
  • C AC circuits
  • D Full wave rectifier circuit

Explanation:

Question 311: X-rays are similar in nature to_______________?

  • A ?-rays
  • B Beta rays
  • C Positive rays
  • D Cathode rays

Explanation:

Question 312: A cup of milk is placed in a microwave oven. Tell which statements is false. (1) Milk will be heated up only. (2) Cup will remain cool. (3) Both cup and mild will get hot ?

  • A 3
  • B 2
  • C 1
  • D None

Explanation:

Question 313: Unit vector n^ is along______________?

  • A Normal on a surface
  • B Y-axis
  • C Z-axis
  • D X-axis

Explanation:

Question 314: X-rays are diffracted by a crystal but not by a diffraction grating because_____________?

  • A The lines in a diffraction grating cannot reflect X-rays.
  • B The wavelengths of X-rays are of the same order of magnitude as the separation between atoms in a crystal
  • C The ions in a crystal are well arranged
  • D The penetration power of X-rays is high in a diffraction grating

Explanation:

Question 315: If A=Ax i^ + Ay j^ + Az K^ B = Bx i^ + By j^ + Bz K^ then______________?

  • A A. B = Ay Bz + Az By + Az Bx
  • B A. B = Ax Bx + Ay By + Az Bz
  • C A. B = Ax By + Ay Bz + Az By
  • D A. B = Ax Bz + Ay By + Az Bx

Explanation:

Question 316: For chain reaction to build up the size of the radioactive target should be______________?

  • A All of above can build up a change reaction
  • B Greater than the critical size
  • C Equal to the critical size
  • D Less than the critical size

Explanation:

Question 317: A million electron are added to a pith ball. Its charge is________?

  • A
  • B
  • C
  • D

Explanation:

Question 318: Earth

  • A 70 km/s
  • B 45 km/s
  • C 60 km/s
  • D 30 km/s

Explanation:

Question 319: The frequency of the second pendulum is________________?

  • A 1 hertz
  • B 0.5 hertz
  • C 1.5 hertz
  • D 2.5 hertz

Explanation:

Question 320: Due to the relative motion of observer and frame of reference time:

  • A Constant
  • B Dilates
  • C Contracts
  • D Uniform

Explanation:

Question 321: Ina liquid metal fast breeder reactor, the type of uranium used is______________?

  • A 92U238
  • B 92U239
  • C 92U235
  • D 92U234

Explanation:

Question 322: If a diffraction grating is placed in the path of a light beam it reveals______________?

  • A Wave property
  • B Electromagnetic wave property
  • C Energy particle
  • D Particle property

Explanation:

Question 323: The minimum wavelength of X-rays produced by the bombardment of electrons on the screen of a television set where the accelerating potential is 2.0K V will be______________?

  • A 3.11 x 10-10m
  • B 6.2 x 10-10m
  • C 9.1 x 10-18m
  • D 4 x 10-10m

Explanation:

Question 324: When K.E energy of SHM is maximum its__________________?

  • A All P.E acceleration and restoring force are zero
  • B Restoring force is zero
  • C Acceleration is zero
  • D P.E is zero

Explanation:

Question 325: The standard vector symbol for flux density is ____________________?

  • A M
  • B H
  • C L
  • D B

Explanation:

Question 326: Thermions are________________?

  • A protons
  • B photons
  • C positrons
  • D electrons

Explanation:

Question 327: An A.C series circuit containing 4? resistance and 3? inductive reactance. The impedance of the circuit is______________?

  • A 1?
  • B 7?
  • C 5?
  • D 7?

Explanation:

Question 328: Compton effect proves the________________?

  • A Photon theory of light
  • B Wave nature of light
  • C Uncertain nature of light
  • D Dual nature of light

Explanation:

Question 329: CGS system of units is also called __________?

  • A Metric or French system of units
  • B None of these
  • C Metric system
  • D Metric or British system of units

Explanation:

Question 330: One pico stands for_________________?

  • A 10 raised to power -9
  • B 10 raised to power -12
  • C 10 raised to power -15
  • D 10 raised to power -6

Explanation:

Question 331: To obtain a p-type semi-conductor Si Crystal must be doped with foreign atoms whose valency is_____________?

  • A 4
  • B 5
  • C 3
  • D 2

Explanation:

Question 332: Which of the following pair of forces can produce a resultant of 8N?

  • A 2N & 5N
  • B 20N & 2N
  • C 3N & 6N
  • D 4N & 1N

Explanation:

Question 333: Forward current through a semi conductor diode circuit is due to____________?

  • A holes
  • B electron
  • C minority carriers
  • D majority carriers

Explanation:

Question 334: pure resistor circuit the voltage and current are_______________?

  • A Lagging each other
  • B No phase difference
  • C They are at 90? phase difference
  • D They have zero phase difference

Explanation:

Question 335: Terminal velocity is_____________?

  • A Neither uniform nor maximum
  • B Maximum
  • C Uniform
  • D Uniform and maximum

Explanation:

Question 336: Which one of the following possesses greater penetration power ?

  • A Neutron-rays
  • B ?-rays
  • C ?-rays
  • D ?-rays

Explanation:

Question 337: Electron moves in the orbit as________________?

  • A S.H.M likes the sound
  • B Vibratory motion like up and down
  • C Standing wave motion
  • D Simple vibratory motion

Explanation:

Question 338: The device or circuit used for conversion of A.C. into D.C. is called_______________?

  • A An amplifier.
  • B A rectifier
  • C Converter.
  • D Filtering circuit

Explanation:

Question 339: The working of transistor as amplifier is similar to________________?

  • A Step up transformer
  • B Triode vacuum tube
  • C Step down transformer
  • D Three diodes in common

Explanation:

Question 340: Acceptor and donor impurities donate______________?

  • A n-carriers only
  • B p-carriers and n-carriers respectively
  • C p-carriers only
  • D n-carriers and p-carriers respectively

Explanation:

Question 341: Bernoulli

  • A None of these
  • B Laminar flow
  • C Both laminar and turbulent flow
  • D Turbulent flow

Explanation:

Question 342: In S.H.M. the velocity of a particle is maximum at________________?

  • A middle between the mean and extreme position on the right side
  • B extreme position
  • C middle between the mean and extreme position on the left side
  • D mean position

Explanation:

Question 343: Radioactive decay obeys which one of the following law ?

  • A N=Noe-?t
  • B N=Noe?t
  • C N=Noe-?t/2
  • D No=N(1+e?t)

Explanation:

Question 344: Metabolism is the name of a process in which energy transformation takes place within______________?

  • A Heat engine
  • B Laboratory
  • C Human body
  • D Atmosphere

Explanation:

Question 345: The equation of continuity is obtained by applying in the law of conservation of_____________?

  • A Momentum
  • B Energy
  • C All
  • D Mass

Explanation:

Question 346: In full wave rectification the output D.C. voltage across the load is obtained for_____________?

  • A The complete cycle of input A.C.
  • B The negative half cycle of input A.C.
  • C The positive half cycle of input A.C.
  • D All of the above.

Explanation:

Question 347: Sphygmomanometers measures blood pressure ?

  • A Statically
  • B None of these
  • C Some time static and sometimes dynamic
  • D Dynamically

Explanation:

Question 348: A black body has the property to _____________ all the radiation entering it.

  • A Reflect
  • B None of these
  • C Absorb
  • D Exude

Explanation:

Question 349: Which of the following radiations are suitable for the treatment of an infection in the interior of the body ?

  • A ?-rays
  • B ?-rays
  • C X-rays
  • D ?-rays

Explanation:

Question 350: A capacitor of capacitance 30

  • A 0.9sec
  • B 0.9x102sec
  • C 1.5x105sec
  • D 15 sec

Explanation: