Home
Class 12
PHYSICS
In the circuit shown in Fig. Sliding con...

In the circuit shown in Fig. Sliding contact is moving with uniform velocity towards right. Its value at some instance is `12 (Omega)`. The current in the circuit at this instant of time will be

A

`0.5A`

B

More than `0.5A`

C

Less than `0.5A`

D

May be less (or) more than `0.5A` depending on value of 'L'

Text Solution

Verified by Experts

The correct Answer is:
B
When 'R' increases 'I' decreases so `di//dt` is-ve.
`i=(6-Ldi//dt)/(12)`
`di/dt "negative" I gt 0.5`
Promotional Banner

Topper's Solved these Questions

  • TEST PAPERS

    ALLEN |Exercise PHYSICS|16 Videos

  • TEST PAPERS

    ALLEN |Exercise MATHS|1 Videos

  • TEST PAPERS

    ALLEN |Exercise part-2 physics|73 Videos

  • TEST PAPER 4

    ALLEN |Exercise PHYSICS|45 Videos

  • UNIT & DIMENSIONS, BASIC MATHS AND VECTOR

    ALLEN |Exercise Exercise (J-A)|7 Videos

Similar Questions

Explore conceptually related problems

Blocks shown in figure moves with constant velocity 10 m/s towards right. All surgaces in contact are rough. The friction force applied by B on A is :-

Two bodies A and B of masses m and 2 m respectively are placed on a smooth floor. They are connected by a spring. A third body C of mass m moves with velocity v_0 along the line joining A and B and collides elastically with A as shown in Fig. At a certain instant of time t_0 after collision, it is found that the instantaneous velocities of A and B are the same. Further at this instant the compression of the spring is found to be x_0 . Determine (i) the common velocity of A and B at time t_0 , and (ii) the spring constant.

Assertion:- Time constants of the cirucits shown in the figure are same. Reason:- Instantaneous current through the capacitor branch is same at any instant for both the circuits, if batteries are inserted in the circuits at t=0

In the circuit shown in Fig.6.2, the heat produced in 5Omega resistor, due to the current flowing through it is 10 calorie per second. Find the heat produced in 4Omega resistor.

A magnetic field vecB=B_0 sin (omegat)hatk covers a large region where a wire AB slides smoothly over two parallel conductors separated by a distance d as in figure. The wires are in the xy-plane. The wire AB (of length d) has resistance R and the parallel wires have negligible resistance. If AB is moving with velocity v, what is the current in the circuit. What is the force needed to keep the wire moving at constant velocity ?

A horizontal platform is rotating with uniform angular velocity around the vertical axis passing through its centre. At some instant of time a viscous fluid of mass m is dropped a the centre and is allowed to spread out and finally fall. The angular velocity during this period ...........

One conducing U tube can be slide inside another as shown in figure, maintaining electrical contacts between the tubes. The magnetic field B is perpendicular to the plane of the figure. If each tube moves towards the other at a constant speed v, then the emf induced in the circuit in terms of B, l and v where l is the width of each tube, will be ........

An experimental setup of verification of photoelectric effect is shown in the diagram. The voltage across the electrode is measured with the help of an ideal voltmetar, and which can be varied by moving jockey 'J' on the potentiometer wire. The battery used in potentiometer circuit is of 20 V and its internal resistance is 2omega . The resistance of 100 cm long potentiometer wire is 8 omega . The photo current is measured with the help of an ideal ammeter. Two plates of potassium oxide of area 50 cm^(2) at separation 0.5 mm are used in the vacuum tube. Photo current in the circuit is very small so we can treat potentiometer circuit an indepdent circuit. The wavelength of various colours is as follows : |{:("Light",underset("Violet")(1),underset("Blue")(2),underset("Green")(3),underset("Yellow")(4),underset("Orange")(5),underset("Red")(6)),(lambda "in" Årarr,4000-4500,4500-5000,5000-5500,5500-6000,6000-6500,6500-7000):}| It is found that ammeter current remians unchanged (2muA) even when the jockey is moved from the 'P' to the middle point of the potentiometer wire. Assuming all the incident photons eject electron and the power of the light incident is 4 xx 10^(-6) W . Then colour of the incident light is :

An experimental setup of verification of photoelectric effect is shown in the diagram. The voltage across the electrode is measured with the help of an ideal voltmetar, and which can be varied by moving jockey 'J' on the potentiometer wire. The battery used in potentiometer circuit is of 20 V and its internal resistance is 2omega . The resistance of 100 cm long potentiometer wire is 8 omega . The photo current is measured with the help of an ideal ammeter. Two plates of potassium oxide of area 50 cm^(2) at separation 0.5 mm are used in the vacuum tube. Photo current in the circuit is very small so we can treat potentiometer circuit an indepdent circuit. The wavelength of various colours is as follows : |{:("Light",underset("Violet")(1),underset("Blue")(2),underset("Green")(3),underset("Yellow")(4),underset("Orange")(5),underset("Red")(6)),(lambda "in" Årarr,4000-4500,4500-5000,5000-5500,5500-6000,6000-6500,6500-7000):}| When other light falls on the anode plate the ammeter reading remains zero till, jockey till, jockey is moved from the end P to the middle point on the wire PQ. Thereafter the deflection is recorded in the ammeter. The maximum kinetic energy of the emitted electron is :

An experimental setup of verification of photoelectric effect is shown in the diagram. The voltage across the electrode is measured with the help of an ideal voltmetar, and which can be varied by moving jockey 'J' on the potentiometer wire. The battery used in potentiometer circuit is of 20 V and its internal resistance is 2omega . The resistance of 100 cm long potentiometer wire is 8 omega . The photo current is measured with the help of an ideal ammeter. Two plates of potassium oxide of area 50 cm^(2) at separation 0.5 mm are used in the vacuum tube. Photo current in the circuit is very small so we can treat potentiometer circuit an indepdent circuit. The wavelength of various colours is as follows : |{:("Light",underset("Violet")(1),underset("Blue")(2),underset("Green")(3),underset("Yellow")(4),underset("Orange")(5),underset("Red")(6)),(lambda "in" Årarr,4000-4500,4500-5000,5000-5500,5500-6000,6000-6500,6500-7000):}| When radiation falls on the cathode plate a current of 2muA is recorded in the ammeter. Assuming that the vecuum tube setup follows ohm's law, the equivalent resistance of vacuum tube operating in this case when jockey is at end P.

ALLEN -TEST PAPERS-part-2 physic
  1. A container having two immiscible liquids of densities 'p' and '2p' mo...

    Text Solution

    |

  2. A non viscous liquid of constant density 10^(3) kg//m^(3) flows in st...

    Text Solution

    |

  3. A uniform thin rod is bent in the form of closed loop ABCDEFA as shown...

    Text Solution

    |

  4. Find force required to keep the system in equilibrium. The dimension o...

    Text Solution

    |

  5. A solid homogeneous sphere is moving on a rough horizontal surface, pa...

    Text Solution

    |

  6. Two current carrying coil having radius 'r' are seperated by distance ...

    Text Solution

    |

  7. The magnetic field in a region is given by vec(B)=B(0)(1+(x)/(a))hat(k...

    Text Solution

    |

  8. In the circuit shown in Fig. Sliding contact is moving with uniform ve...

    Text Solution

    |

  9. A bulb of 100 W is connected in parallel to an ideal inductance of 1H....

    Text Solution

    |

  10. A ray of light is incident on the surface of a sphere of refractive in...

    Text Solution

    |

  11. A cylindrical tank of base area A has a small hole of areal a at the b...

    Text Solution

    |

  12. A ring of mass 'm' and radius 'r' carrying current i(0) is lying in t...

    Text Solution

    |

  13. In the circuit shown in figure power factor of box is 0.5 and power fa...

    Text Solution

    |

  14. A parabolic mirror is silvered at inner surface. The equation of the c...

    Text Solution

    |

  15. A heavy and a light cylindrical rollers of diameter D and d respectiv...

    Text Solution

    |

  16. Figure shows the graph of angle of deviation del versus angle of incid...

    Text Solution

    |

  17. A plank P is placed on a solid cylinder S, which rolls on a horizontal...

    Text Solution

    |

  18. An object to the left of a lens is imaged by the lens on a screen 30cm...

    Text Solution

    |

  19. A direct current of 2 A and an alternating current having a maximum va...

    Text Solution

    |

  20. The potential difference across a 4 H inductor vary with time is as sh...

    Text Solution

    |