## Physics

### Physics HSC Maharastra Board Multiple Choice Question With Answer

**1) A diver in a swimming pool bends his head before diving. It ______**

A) Increases his linear velocityB) Decreases his angular velocityC) Increases his moment of inertiaD) Decreases his moment of inertia

Ans : Decreases his moment of inertia

**2) The angular momentum of a system of particles is conserved ______**

A) When no external force acts upon the systemB) When no external torque acts upon the systemC) When no external impulse acts upon the systemD) When the axis of rotation remains the same

Ans : When no external torque acts upon the system

**3) A stone is tied to one end of a string. Holding the other end, the string is whirled in a horizontal plane with progressively increasing speed. It breaks at some speed because ______**

A) The gravitational forces of the earth are greater than the tension in the stringB) The required centripetal force is greater than the tension sustained by the stringC) The required centripetal force is lesser than the tension in the stringD) The centripetal force is greater than the weight of the stone

Ans : The required centripetal force is greater than the tension sustained by the string

**4) The moment of inertia of a circular loop of radius R, at a distance of R/2 around a rotating axis parallel to horizontal diameter of the loop is ______**

A) ½ MR2B) ¾ MR2C) MR2D) 2MR2

Ans : ¾ MR2

**5) A 500 kg car takes a round turn of the radius of 50m with a velocity of 36 km/hr. The centripetal force is ______**

A) 250NB) 750NC) 1000ND) 1200N

Ans : 1000N

**6) A string of length ℓ fixed at one end carries a mass m at the other. The string makes 2/π revolutions/sec around the vertical axis through the fixed end. The tension in the string is ______**

A) 2 mlB) 4 mlC) 8 mlD) 16 ml

Ans : 16 ml

**7) Insect moves over the surface of water because of ______**

A) ElasticityB) Surface tensionC) FrictionD) Viscosity

Ans : Surface tension

**8) The water droplets are spherical in free fall due to ______**

A) GravityB) Intermolecular attractionC) Surface tensionD) Viscosity

Ans : Gravity

**9) The surface tension of a liquid at critical temperature is ______**

A) InfinityB) ZeroC) Same as any other temperatureD) Can not be determined

Ans : Zero

**10) Unit of the coefficient of viscosity is ______**

A) Ns/mB) Ns2/mC) Ns2/m2D) Ns/m2

Ans : Ns/m2

**11) Two capillary tubes of radii 0.6 cm and 0.3 cm are dipped in the same liquid. The ratio of heights through which the liquid will rise in the tubes is ______**

A) 2:1B) 1:2C) 4:1D) 1:4

Ans : 1:2

**12) Two stones with radii 1:2 fall from a great height through the atmosphere. Their terminal velocities are in the ratio ______**

A) 2:1B) 1:4C) 4:1D) 1:2

Ans : 1:4

**13) The average energy per molecule is proportional to ______**

A) The pressure of the gasB) The volume of the gasC) The absolute temperature of the gasD) The mass of the gas

Ans : The absolute temperature of the gas

**14) The number of degrees of freedom, for the vibrational motion of a polyatomic molecule, depends on the ______**

A) Geometric structure of the moleculeB) Mass of the moleculeC) The energy of the moleculeD) The absolute temperature of the molecule

Ans : Geometric structure of the molecule

**15) The power radiated by a perfect blackbody depends only on its ______**

A) MaterialB) Nature of surfaceC) ColourD) Temperature

Ans : Temperature

**16) If the absolute temperature of a body is doubled, the power radiated will increase by a factor of ______**

A) 2B) 4C) 8D) 16

Ans : 16

**17) Calculate the value of λmax for radiation from a body having a surface temperature of 3000 K. (b = 2.897 x 10-3 m K)**

A) 9935 ÅB) 9656 ÅC) 9421 ÅD) 9178 Å

Ans : 9656 Å

**18) Calculate the energy radiated in one minute by a blackbody of surface area 200 cm2 at 127 °C (σ = 5.7 x 10-8 J m-2 s-1 K-4)**

A) 1367.04 JB) 1698.04 JC) 1751.04 JD) 1856.04 J

Ans : 1751.04 J

**19) Which of the following is correct, when the energy is transferred to a system from its environment?**

A) System gains energyB) System loses energyC) System releases energyD) The system does not exchange energy

Ans : System gains energy

**20) Which of the following system freely allows the exchange of energy and matter with its environment?**

A) ClosedB) IsolatedC) OpenD) Partially closed

Ans : Open

**21) Two systems at the same temperature are said to be in ______**

A) Chemical equilibriumB) Thermal equilibriumC) Mechanical equilibriumD) Electrical equilibrium

Ans : Thermal equilibrium

**22) For work done to be reversible, the process should be ______**

A) CyclicB) IsobaricC) IsochoricD) Adiabatic

Ans : Adiabatic

**23) The second law of thermodynamics deals with the transfer of ______**

A) Work doneB) EnergyC) MomentumD) Heat

Ans : Heat

**24) Heating a gas in a constant volume container is an example of which process?**

A) IsochoricB) AdiabaticC) IsobaricD) Cyclic

Ans : Isochoric

**25) A particle is moving in a circle with uniform speed. Its motion is ______**

A) Periodic and simple harmonicB) Non-periodicC) Periodic but not simple harmonicD) Non-periodic but simple harmonic

Ans : Periodic but not simple harmonic

**26) Acceleration of a particle executing S.H.M. at its mean position.**

A) Is infinityB) VariesC) Is maximumD) Is zero

Ans : Is zero

**27) In a second’s pendulum, the mass of Bob is 50 g. If it is replaced by 100 g mass, then its period will be ______.**

A) 1 sB) 2 sC) 3 sD) 4 s

Ans : 2 s

**28) The maximum speed of a particle executing S.H.M. is 10 m/s and maximum acceleration is 31.4 m/s2. Its periodic time is ______**

A) 1 sB) 2 sC) 4 sD) 6 s

Ans : 2 s

**29) When the displacement of a simple harmonic oscillator is half of its amplitude, its P.E. is 3 J. Its total energy is ______**

A) 6 JB) 12 JC) 15 JD) 20 J

Ans : 12 J

**30) A standing wave is produced on a string fixed at one end with the other end free. The length of the string ______**

A) Must be an odd integral multiple of λB) Must be an odd integral multiple of λ/2C) Must be an odd integral multiple of λ/4D) Must be an even integer multiple of λ

Ans : Must be an odd integral multiple of λ/4

**31) The equation of a simple harmonic progressive wave is given by, y = 5 cos π [200t – x/150], where x and y are in cm and ‘t’ is in second. Then the velocity of the wave is ______**

A) 2 m/sB) 150 m/sC) 200 m/sD) 300 m/s

Ans : 200 m/s

**32) In the law of tension, the fundamental frequency of the vibrating string is, ______**

A) Inversely proportional to the square root of tensionB) Directly proportional to the square of tensionC) Directly proportional to the square root of tensionD) Inversely proportional to the density

Ans : Directly proportional to the square root of tension

**33) The integral multiple of fundamental frequencies are ______**

A) BeatsB) ResonanceC) OvertonesD) Harmonics

Ans : Harmonics

**34) An organ pipe of length 0.4 m is open at both ends. The speed of sound in the air is 340 m/s. The fundamental frequency is ______**

A) 405 HzB) 415 HzC) 425 HzD) 435 Hz

Ans : 425 Hz

**35) When light travels from an optically rarer medium to an optically denser medium, the speed decreases because of change in ______**

A) WavelengthB) FrequencyC) AmplitudeD) Phase

Ans : Wavelength

**36) Light follows wave nature because ______**

A) Light rays travel in a straight lineB) Light exhibits the phenomenon of reflection and refractionC) Light exhibits the phenomenon of interferenceD) Light causes the phenomenon of the photoelectric effect

Ans : Light exhibits the phenomenon of interference

**37) Which of the following cannot produce two coherent sources?**

A) Lloyd’s mirrorB) Fresnel biprismC) Young’s double-slitD) Prism

Ans : Prism

**38) The bending of a beam of light around corners of obstacle is called ______**

A) ReflectionB) DiffractionC) RefractionD) Interference

Ans : Diffraction

**39) Kirchhoff’s second law (voltage law) is based on ______**

A) Conservation of chargeB) Conservation of massC) Conservation of energyD) Conservation of momentum

Ans : Conservation of energy

**40) The SI unit of the potential gradient is ______**

A) V/cmB) V-mC) V/mD) V-cm

Ans : V/m

**41) The instrument which can measure terminal potential difference as well as electromotive force (emf) is ______**

A) Wheatstone’s meter bridgeB) VoltmeterC) PotentiometerD) Galvanometer

Ans : Potentiometer

**42) When the null point is obtained in the potentiometer, the current is drawn from the ______**

A) Main batteryB) Cell batteryC) Both main and cell batteryD) Neither main nor cell battery

Ans : Main battery

**43) If the potential gradient of a wire decreases, then its length ______**

A) Remains constantB) DecreasesC) IncreasesD) None of the above

Ans : Increases

**44) According to the right-hand rule, the direction of magnetic induction if the current is directed in an anticlockwise direction is ______**

A) Perpendicular and inwardsB) Perpendicular and outwardsC) Same as currentD) Opposite to that of current

Ans : Perpendicular and outwards

**45) A strong magnetic field is applied to a stationary electron. Then the electron ______**

A) Moves in the direction of the fieldB) Remained stationaryC) Moves perpendicular to the direction of the fieldD) Moves opposite to the direction of the field

Ans : Remained stationary

**46) The force between two parallel current-carrying conductors is F. If the current in each conductor is doubled, then the force between them becomes ______**

A) 4FB) 2FC) FD) F/4

Ans : 4F

**47) Which of the following is not a unit of magnetic induction?**

A) GuassB) TeslaC) OerstedD) Wb/m2

Ans : Oersted

**48) The magnetic dipole moment of the current loop is independent of ______**

A) Number of turnsB) Area of loopC) Current in the loopD) The magnetic field in which it is lying

Ans : The magnetic field in which it is lying

**49) Which of the following is correct, when the energy is transferred to a system from its environment?**

A) System gains energyB) System loses energyC) System releases energyD) The system does not exchange energy

Ans : System gains energy

**50) Two systems at the same temperature are said to be in ______**

A) Chemical equilibriumB) Thermal equilibriumC) Mechanical equilibriumD) Electrical equilibrium

Ans : Thermal equilibrium