Physics Questions And Answers

71.Two teams are puling a rope with equal and opposite forces each of 5 KN  in a tug of war so that a condition of equilibrium exists. What will be the tensile force in the rope ? 
a. zeri 
b. 2.5 KN 
c. 5KN 
d. 10 KN 

Cover The answer.
Answer: 5KN 


72. Scalars are quantities that are described by ____
a. Magnitude
b. Direction
c. Magnitude & Direction
d. Motion

Cover The answer
ANSWER: a. Magnitude



73.The ionization potential of hydrogen is 13.6 eV. The energy of an electron in the second orbit is
a. 54.4 eV
b. -6.8 eV
c. -27.2 eV
d. -3.4 eV

Cover The answer
ANSWER : : -3.4 eV



74. Which of the following measurements is not a unit of distance?  
A.  Ammeter
B.  Cubit
C.  Parsec
D.  angstrom

Cover The answer
Answer : A.  Ammeter



75. Rate of change of momentum is called?
A. Force                               
B. Pressure                         
C. Velocity                           
D. Speed             

Cover The answer
Answer. A





76. A satellite in vacuum -
1. Is kept in orbit by remote control
2. Is kept in orbit by retro-rocket
3. Derives energy from gravitational field
4. Does not require any energy for orbiting

Cover The answer
Ans: 4




77. Radiocarbon is produced in the atmosphere as a result of
A. collision between fast neutrons and nitrogen nuclei present in the atmosphere
B. action of ultraviolet light from the sun on atmospheric oxygen
C. action of solar radiations particularly cosmic rays on carbon dioxide present in the atmosphere
D. lightning discharge in atmosphere

Cover The answer
Answer: A



78. The most suitable unit for expressing nuclear radius is
A) micro
B) nanometre
C) fermi
D) angstrom

Cover The answer
Answer  C) fermi 



79. Which one of the following is used as a moderator in nuclear reactor
A. radium
B. graphite
C. thorium
D. ordinary water

Cover The answer
Answer  B



80. On which one of the following conservation laws, does a rocket work?  
A.  Mass
B.  Energy
C.  Linear momentum
D.  Angular momentum

Cover The answer
Answer : c.  Linear momentum



81. The unit of pressure is -
A.  Kg / cm2
B.  Kg / cm
C.  Kg / mm
D.  Nm

Cover The answer
Answer: B.  Kg / cm



82. 
How much heat is required to raise the temperature of 1g of water by 1 oC.   
a. 100 Joules
b. 100 Calories  Wrong!
c. 1 Calorie Right!
d. 1 Joule

Cover The answer
Answer: c


83. One radian is defined to be the angle subtended where the arc length “S” is exactly equal to the?
a.  half of radius of the circle.
b.  diameter of the circle.
c.  radius of the circle.
d.  circumference of the circle.

Cover The answer
Answer: c



84. Name the device which converts electric energy into mechanical energy : 
a. alternator
b. transformer
c. dynamo
d. motor

Cover The answer
Answer: d


For more click here 43- 70