131: F = q B×V the presents the force exerted on a

a) Charge q moving with velocity v in a electric field

b) Charge q moving with velocity v in a magnetic field B

c) Both

d) None of these

132: Biot_savart’s law is expressed mathematically as

a) H

b) B ∝ Idlsin∅/r2

c) Hdl=Ienc

d) Hdl=(∇×H)ds

133: Biot_savart’s law can be applied to current carrying conductors of

a) Large length

b) Medium length

c) Small length

d) Very small length

134: potential has the unit of

a) J/C

b) Joule

c) J/m3

d) J/m2

135: according to Ampere’s circuital law, field intensity at a point at distance R from a very 

long straight Fila

a) Hdl=Ienc

b) Jds=I

c) Both a & b

d) None of these

136: Ampere’s circuital law and which of the following law in electrostatics are analogous

a) Lenz’s

b) Gauss’s

c) Boit_savart’s

d) Faraday’s

137: Ampere’s circuital law can be applied …… the conductor

a) Inside

b) Outside

c) Both a & b

d) None of these

138: electric intensity at any point in an electric field is equal the at that point

a) Electric flux

b) Magnetic flux density

c) Potential gradient

d) None of the above

139: when a dielectric material is placed in an electrictric field it

a) Is charged

b) Get polarized

c) Remain un charged

d) Remain un polarized

140: an electromagnetic field exit only when there is

a) An increasing current

b) Decreasing current

c) Voltage

d) Current

141: when a dielectric placed in an electric field the field strength is

a) Decrease

b) Increase

c) Reduce to zero

d) Remain un changed

142: according to Ampere’s circuital law,

a) Hdl=Ienc

b)Jds=I

c) Hdl=∇×Hds

d) ∇×E=-∂B/∂t

143: a magnetic field exist around

a) Iron

b) Copper

c) Aluminium

d) Moving charge

144: electric potential V is given by

a) E=-∇V

b) V=Q/4πεr

c) Both a & b

d) None of these

145: magnetic field outside a solenoid is

a) Zero

b) Strong

c) Infinity

d) Negligible

146: the unit for permeability is

a) Wb

b) At/m

c) Web/At×m

d) At/web

147: the unit of electric dipole moment of

a) C.m

b) C/m

c) C.m2

d) C/m2

148: a field line and an equipotential of surface are

a) Always parallel

b) Always at 90 degree

c) Inclined at any angle

d) None of these

149: the force between two charge each of charge one micro colomb placed one meter aparts

in air will be

a) 9*10-12 N

b) 9*10+12 N

c) Zerod) 9*10-3 N

150: gauss law is applicable for a

a) Curved surface

b) Closed surface

c) Rectangular surface

d) Equipotential surface