An electron moves on a straight line path XY as shown. The abcd

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsMultiple Choice Questions

171.

The electric and the magnetic field, associated with an electromagnetic wave, propagating along the +z - axis, can be represented by

  • left square bracket bold E space equals space straight E subscript straight o bold k with hat on top comma space bold B space equals space straight B subscript straight o space bold i with hat on top right square bracket
  • left square bracket bold E space equals space straight E subscript straight o bold j with hat on top comma space bold B space equals space straight B subscript straight o space bold j with hat on top right square bracket
  • left square bracket bold E space equals space straight E subscript straight o bold j with hat on top comma space bold B space equals space straight B subscript straight o space bold k with hat on top right square bracket
  • left square bracket bold E space equals space straight E subscript straight o bold j with hat on top comma space bold B space equals space straight B subscript straight o space bold k with hat on top right square bracket
390 Views

172.

A proton and an alpha particle both enter a region of uniform magnetic field B, moving at angles to the field B. If the radius of circular orbits for both the particles is equal and the kinetic energy acquired by proton is 1 MeV, the energy acquired by the alpha particle will be

  • 4 MeV

  • 0.5 Mev

  • 1.5 MeV

  • 1.5 MeV

3395 Views

173.

Two metal wires of identical dimensions are connected in series if σ1a nd σ2 are the conductivity of the metal wires respectively, the conductivity of the combination is 

  • fraction numerator 2 straight sigma subscript 1 straight sigma subscript 2 over denominator straight sigma subscript 2 space plus straight sigma subscript 2 end fraction
  • fraction numerator straight sigma subscript 1 space plus straight sigma subscript 2 over denominator 2 space straight sigma subscript 1 straight sigma subscript 2 end fraction
  • fraction numerator straight sigma subscript 1 space plus straight sigma subscript 2 over denominator straight sigma subscript 1 straight sigma subscript 2 end fraction
  • fraction numerator straight sigma subscript 1 space plus straight sigma subscript 2 over denominator straight sigma subscript 1 straight sigma subscript 2 end fraction
3220 Views

Advertisement

174.

An electron moves on a straight line path XY as shown. The abcd is a coil adjacent in the path of the electron. What will be the direction of the current, if any induced in the coil?

  • abcd

  • adcb

  • the current will reverse its direction as the electron goes past the coil

  • the current will reverse its direction as the electron goes past the coil


C.

the current will reverse its direction as the electron goes past the coil

First current develops in direction of abcd but when electron moves away then magnetic field inside loop decrease and current changes its direction.

1402 Views

Advertisement
Advertisement
175.

A galvanometer of resistance, G is shunted by a resistance S ohm. To keep the main current in the circuit unchanged,the resistance to be put in series with the galvanometer is

  • fraction numerator straight S squared over denominator left parenthesis straight S space plus straight G right parenthesis end fraction
  • fraction numerator SG over denominator left parenthesis straight S plus straight G right parenthesis end fraction
  • fraction numerator straight G squared over denominator left parenthesis straight S space plus straight G right parenthesis end fraction
  • fraction numerator straight G squared over denominator left parenthesis straight S space plus straight G right parenthesis end fraction
1479 Views

176.

A thermocouple force towards the conductor produces an emf of 40 μ V/oC in the linear range of temperature. A galvanometer of resistance 10 Ω whose sensitivity is 1μA/div, is employed with the thermocouple. The smallest value of temperature difference that can be detected by the system will be.

  • 0.5oC

  • 1oC

  • 0.1oC

  • 0.1oC

300 Views

177.

Charge q is uniformly spread on a thin ring of radius R. The ring rotates about its axis with a uniform frequency f Hz. The magnitude of magnetic induction at the centre of the ring is 

  • μoqf  / 2R

  • μoq / 2fR

  • μoq / 2πfR

  • μoq / 2πfR

372 Views

178.

A short bar magnet of magnetic moment 0.4 JT-1 is placed in a uniform magnetic field of 0.16T. The magnet is stable equilibrium when the potential energy is

  • -0.64 J

  • zero

  • -0.082 J

  • -0.082 J

397 Views

Advertisement
179.

A potentiometer circuit is set up as shown. The potential gradient across the potentiometer wire is k volt /cm and the ammeter, present in the circuit, reads 1.0 A when the two-way key is switched off. The balance points, when the key between the terminals (i) 1 and 2 (ii) 1 and 3, is plugged in, are found to be at lengths  l1 and l2 cm respectively. The magnitudes, of the resistor R and X, in ohm, are then, equal respectively, to

 

  • k (l2 -l1) and kl2

  • kl1 and k (l2-l1)

  • k (l2 - l1) and kl1

  • k (l2 - l1) and kl1

1223 Views

180.

A galvanometer has a coil of resistance 100 Ω and gives a full-scale deflection for 30 mA current. If it is to work as a voltmeter of 30 V range, the resistance required to be added will be

  • 900 Ω

  • 1800

  • 500 Ω

  • 500 Ω

499 Views

Advertisement