Basic Physics Mcqs - Set 3

1)   Increase in velocity of sound in the air for 1°C rise in temperature is_________________?

a. 1.61 ms-1
b. 61.0 ms-1
c. 0.61 ms-1
d. 2.00 ms-1
Answer  Explanation 

ANSWER: 0.61 ms-1

Explanation:
No explanation is available for this question!


2)   On loading the prong of a tuning form with wax its frequency____________________?

a. increases
b. decreases
c. remains unchanged
d. may increase or decrease
Answer  Explanation 

ANSWER: decreases

Explanation:
No explanation is available for this question!


3)   The normal ear is the most sensitive in the frequency range___________________?

a. 20000 to 30000 hertz
b. 10 to 20 hertz
c. 2000 to 4000 hertz
d. 6000 to 8000 hertz
Answer  Explanation 

ANSWER: 2000 to 4000 hertz

Explanation:
No explanation is available for this question!


4)   The velocity of sound in air would become double than its velocity at 0°C at temperature________________?

a. 313°C
b. 586°C
c. 819°C
d. 1172°C
Answer  Explanation 

ANSWER: 819°C

Explanation:
No explanation is available for this question!


5)   The periodic alternation of sound between maximum and minimum loudness are called___________________?

a. silence zone
b. interference
c. beats
d. resonance
Answer  Explanation 

ANSWER: beats

Explanation:
No explanation is available for this question!


6)   Beats are the results of____________________?

a. diffraction of sound waves
b. constructive and destructive interference
c. polarization
d. destructive interference
Answer  Explanation 

ANSWER: constructive and destructive interference

Explanation:
No explanation is available for this question!


7)   Doppler effect applies to____________________?

a. sound wave only
b. light wave only
c. both sound and light waves
d. neither sound nor light wave
Answer  Explanation 

ANSWER: both sound and light waves

Explanation:
No explanation is available for this question!


8)   A simple pendulum has a bob of mass m and its frequency is f. If we replaced the bob with a heavier one say of 2m then that will be its new frequency ?

a. 1/4f
b. 1/2f
c. frequency lower than 20 Hz
d. 2f
Answer  Explanation 

ANSWER: frequency lower than 20 Hz

Explanation:
No explanation is available for this question!


9)   In open organ pipe___________________?

a. only even harmonics are present
b. only odd harmonics are present
c. both even and odd harmonics are present
d. selected harmonics are present
Answer  Explanation 

ANSWER: both even and odd harmonics are present

Explanation:
No explanation is available for this question!


10)   The dimension of elastic modulus is ___________________ ?

a. ML-1T-2
b. ML-2T-2
c. MLT-2
d. ML2T-2
Answer  Explanation 

ANSWER: ML-1T-2

Explanation:
No explanation is available for this question!


11)   Waves produced at the surface of water by a pencil executing vibrating motion if held vertically at a frequency of 50Hz are__________________?

a. Longitudinal
b. Transverse
c. Periodic
d. both A and C
Answer  Explanation 

ANSWER: both A and C

Explanation:
No explanation is available for this question!


12)   Laplace found that the alternate compressions and rarefactions produced in sound waves follows ________________?

a. isothermal law
b. adiabatic law
c. isochoric law
d. all of the above
Answer  Explanation 

ANSWER: adiabatic law

Explanation:
No explanation is available for this question!


13)   The beats frequency (sensible) for a human car is _____________________?

a. 42Hz
b. 7 Hz
c. 256Hz
d. 262Hz
Answer  Explanation 

ANSWER: 7 Hz

Explanation:
No explanation is available for this question!


14)   Fundamental frequency of stationary waves in open pipe is ______________ times the frequency in closed pipe?

a. One
b. Two
c. Four time
d. None of these
Answer  Explanation 

ANSWER: Two

Explanation:
No explanation is available for this question!


15)   The current through a metallic conductor is due to the motion of _________________?

a. free electrons
b. protons
c. neutrons
d. still under controversy
Answer  Explanation 

ANSWER: free electrons

Explanation:
No explanation is available for this question!


16)   A wire having very high value of conductance is said to be____________________?

a. very good conductor
b. moderately good conductor
c. an insulator
d. no specific criterion available
Answer  Explanation 

ANSWER: very good conductor

Explanation:
No explanation is available for this question!


17)   Production of heat due to an electric current flowing through a conductor is given by _________________?

a. Joule effect
b. Joule Thomsons effect
c. Comptons effect
d. Feed back effect
Answer  Explanation 

ANSWER: Joule effect

Explanation:
No explanation is available for this question!


18)   Three equal resistors connected in series with a source of e m f together dissipate 10 W of power each. What will be the power dissipated if the same resistors are connected in parallel across the same source of e m f ?

a. 40 W
b. 90W
c. 100W
d. 120W
Answer  Explanation 

ANSWER: 90W

Explanation:
No explanation is available for this question!


19)   Thermocouples convert___________________?

a. heat energy into electrical energy
b. heat energy into light energy
c. heat energy into mechanical energy
d. mechanical energy into heat energy
Answer  Explanation 

ANSWER: heat energy into electrical energy

Explanation:
No explanation is available for this question!


20)   An immersion heater of 400 watts kept on for 5 hours will consume electrical power of __________________?

a. 2KWh
b. 20KWh
c. 6KWh
d. 12KWh
Answer  Explanation 

ANSWER: 2KWh

Explanation:
No explanation is available for this question!


21)   Resistance of an ideal insulator is __________________?

a. infinite
b. zero
c. finite
d. depends upon nature
Answer  Explanation 

ANSWER: infinite

Explanation:
No explanation is available for this question!


22)   Reciprocal of resistivity is called__________________?

a. resistance
b. inductance
c. conductivity
d. flexibility
Answer  Explanation 

ANSWER: conductivity

Explanation:
No explanation is available for this question!


23)   Circuit which gives continuously varying potential is called _______________________?

a. complex network
b. wheat stone bridge
c. potential divider
d. all of above
Answer  Explanation 

ANSWER: potential divider

Explanation:
No explanation is available for this question!


24)   There are three bulbs of 60W 100W and 200W which bulb has thickest filament ?

a. 100W
b. 200W
c. 60W
d. all
Answer  Explanation 

ANSWER: 200W

Explanation:
No explanation is available for this question!


25)   Specific resistance of a wire____________________?

a. will depend on its length
b. will depend on its radius
c. will depend on the type of material of the wire
d. will depend on none of the above
Answer  Explanation 

ANSWER: will depend on the type of material of the wire

Explanation:
No explanation is available for this question!


26)   In the following figure, the terminal potential is ___________________ ?

a. zero
b. 2V
c. 12V
d. 36V
Answer  Explanation 

ANSWER: zero

Explanation:
No explanation is available for this question!


27)   Which one of the following materials is useful for making bulb filaments ?

a. constantan
b. nichrome
c. copper
d. tungsten
Answer  Explanation 

ANSWER: tungsten

Explanation:
No explanation is available for this question!


28)   If 1 ampere current flows through 2m long conductor the charge flow through it in 1 hour will be_______________?

a. 3600C
b. 7200C
c. 1C
d. 2C
Answer  Explanation 

ANSWER: 3600C

Explanation:
No explanation is available for this question!


29)   Why should a resistance be introduced in a circuit in series deliberately ?

a. to increase current
b. to decrease current
c. to control current
d. just to give a good look to circuit
Answer  Explanation 

ANSWER: to decrease current

Explanation:
No explanation is available for this question!


30)   All electrical appliances are connected in parallel to each other between the main line and neutral wire to get ______________________?

a. same current
b. same current and potential difference
c. different current but same potential difference
d. different current and potential differences
Answer  Explanation 

ANSWER: different current but same potential difference

Explanation:
No explanation is available for this question!


31)   Resistance of a conductor depends upon_________________?

a. nature of conductor
b. dimension of conductor
c. physical state of the conductor
d. all of above
Answer  Explanation 

ANSWER: all of above

Explanation:
No explanation is available for this question!


32)   A wire of uniform area of cross-section A length L and resistance R is cut into two parts. Resistivity of each part _________________?

a. remains the same
b. is doubled
c. is halved
d. becomes zero
Answer  Explanation 

ANSWER: remains the same

Explanation:
No explanation is available for this question!


33)   When same current passes for same time through a thick and thin wire_________________?

a. more heat is produced in thick wire
b. more heat is produced in thin wire
c. no heat is produced in wire
d. less heat is produced in thick wire
Answer  Explanation 

ANSWER: more heat is produced in thin wire

Explanation:
No explanation is available for this question!


34)   One kilowatt hour is the amount of energy delivered during _______________?

a. one second
b. one day
c. one minute
d. one hour
Answer  Explanation 

ANSWER: one hour

Explanation:
No explanation is available for this question!


35)   How much heat does a 40 W bulb generates in one hour ?

a. 144000J
b. 144J
c. 1.44J
d. 14J
Answer  Explanation 

ANSWER: 144000J

Explanation:
No explanation is available for this question!


36)   Resistance of a super conductor is ______________________?

a. finite
b. infinite
c. zero
d. changes with every conductor
Answer  Explanation 

ANSWER: zero

Explanation:
No explanation is available for this question!


37)   Which one is the best material for making connecting wires ?

a. iron
b. tungsten
c. silver
d. copper
Answer  Explanation 

ANSWER: copper

Explanation:
No explanation is available for this question!


38)   Internal resistance is the resistance offered by________________?

a. source of EMF
b. conductor
c. resistor
d. capacitor
Answer  Explanation 

ANSWER: source of EMF

Explanation:
No explanation is available for this question!


39)   Three bulbs are rating 40W 60W and 100W designed to work on 220V mains. Which bulb will burn most brightly if they are connected in series across 220 V mains ?

a. 40 W bulb
b. 60 W blub
c. 100 W blub
d. all will burn equally brightly
Answer  Explanation 

ANSWER: 40 W bulb

Explanation:
No explanation is available for this question!


40)   Resistance of a wire on increasing its temperature will_________________?

a. increase with rise in temperature
b. decrease with rise in temperature
c. will remain same
d. depends upon altitude of experimentation
Answer  Explanation 

ANSWER: increase with rise in temperature

Explanation:
No explanation is available for this question!