A bar magnet of dipole moment ’m’ cut into two equal pieces transverse to its length. Dipole moment of each part is
a) Remain same
b) m/2
c) 2m
d) none of the above
a) Remain same
b) m/2
c) 2m
d) none of the above
b) m/2
If a magnet is cut perpendicular its length into equal parts ,then the pole strength of each pole of the magnet
a) becomes double
b) remains same
c) becomes half
d) None of the above
Magnetic field lines form continuous closed loops
a) magnet is always a dipole
b) magnet is always a monopole
c) magnetic material is permeable
d) none of the above
The direction of magnetic dipole moment is always from
a) North pole to south pole
b)Away from North pole outside magnet
c) South pole to North Pole
d) all of the above
Unit of magnetic dipole moment is
a) ampere meter
b) ampere/meter⁻¹
c) ampere metre²
d) ampere/metre²
A current loop placed in a magnetic field behaves like a
a) Magnetic substance
b) Magnetic pole
c) Magnetic dipole
d) all true
A steel wire of length l has a magnetic moment M .It is then bent into a semicircular arc. The new magnetic moment is
a) M
b) 2M/π
c) M/l
d) Ml
What happen when we use white light in Young’s double slit experiment.
(A) No interference pattern will form
(B) white fringes will form
(C) Central bright fringe will be white
(D) Central fringe will be coloured
To obtain a sustained interference pattern we require two sources which emit radiation of
(A) the same frequency
(B) nearly same frequency
(C) the same frequency having a definite phase relationship
(D) different wavelengths
An AC voltage source of variable angular frequency ω and fixed amplitude V connected in series with a capacitance C and an electric bulb of resistance R (inductance zero). When ω is increased
(a) The bulb glows dimmer
(b) The bulb glows brighter
(c) Net impedance of circuit is unchanged
(d) Total impedance of the circuit increases
A capacitor is connected across a battery and the plate separation of capacitor is increased without removing the battery, then:
(a) capacitance will increase
(b) charge stored will increase
(c) energy stored will decrease
(d) potential difference will increase
Electric charge between two bodies can be produced by
(A )Sticking
(B) Rubbing
(C) Oiling
(D) Passing AC current
Unpolarized light is incident on a plane glass surface The angle of incidence so that reflected and refracted rays are perpendicular to each other, them
(a) tan iβ= μ/2
(b) tan iβ = μ
(c) sin iβ = μ
(d) cos iβ = μ
Wavefront is the locus of all points, where the particles of the medium vibrate with the same
(a) phase.
(b) amplitude.
(c) frequency.
(d) period.