# General Science - Physics MCQs

Physics Objective (Multiple Choice) General Knowledge & General Science Questions & Answers for SSC-CGL, UPPSC, UPSC, NDA, CDS and UPSC Civil Services Prelims Examinations.

81. What is the distance between the focus and the pole of the mirror is known as?

[A] Centre of Curvature
[B] Focal length
[C] Mirror number

82. Which of the following are the cases of use of concave mirrors?

[A] Search-lights
[B] Shaving mirrors
[C] Solar furnaces
[D] All of the above

83. What of the following represents Ohm’s law (V= potential difference and I=current)?

[A] V = I 2
[B] V = 1/I
[C] V/I = constant
[D] None of the above

84. What is the equivalent EMF of a series combination of n cells?

[A] the arithmetic mean of their EMFs
[B] the product of their individual EMF
[C] the sum of their individual EMF
[D] None of the above

85. What do we call the electrode that can be oxidized or reduced in half reaction?

[A] Inert electrode
[B] Active electrode
[C] Sleeping electrode
[D] Passive electrode

86. What is the direction of current through external circuit in a galvanic cell?

[A] flows from cathode to anode
[B] flows from anode to cathode
[C] flows in both direction
[D] None of the above

87. Which of the following is correct about magnetic field?

[A] Magnetic field has magnitude but no direction
[B] Magnetic field has both magnitude and direction
[C] Magnetic field may or may not have direction
[D] None of the above

88. What is the relationship between the magnetic field in the straight conductor and the distance from it?

[A] magnetic field decreases as the distance increases
[B] magnetic field increases as the distance increases
[C] magnetic field is independent of the distance
[D] None of the above

89. What is the S.I. unit of magnetic dipole moment?

[A] joule/tesla
[B] joule/metre
[C] tesla/metre
[D] Newton/metre