English

If the Radius of a Sphere is Doubled Without Changing the Charge on It, Then Electric Flux Originating from the Sphere is - Physics

Advertisements
Advertisements

Question

If the radius of a sphere is doubled without changing the charge on it, then electric flux originating from the sphere is ______.

Options

  • double

  • half

  • same

  • zero

MCQ

Solution

same

shaalaa.com
  Is there an error in this question or solution?
2014-2015 (October)

APPEARS IN

RELATED QUESTIONS

Explain the meaning of the term mutual inductance.


Draw a necessary arrangement for winding of primary and secondary coils in a step-up transformer. State its underlying principle and derive the relation between the primary and secondary voltages in terms of number of primary and secondary turns. Mention the two basic assumptions used in obtaining the above relation.


Define mutual inductance.


A 1.0 m long metallic rod is rotated with an angular frequency of 400 rad s−1 about an axis normal to the rod passing through its one end. The other end of the rod is in contact with a circular metallic ring. A constant and uniform magnetic field of 0.5 T parallel to the axis exists everywhere. Calculate the emf developed between the centre and the ring.


Explain self induction and mutual induction


Define coefficient of mutual induction. 


Explain the phenomenon of mutual induction.


A pair of adjacent coils has a mutual inductance of 1.5 H. If the current in one coil changes from 0 to 20 A in 0.5 s, what is the change of flux linkage with the other coil?


Consider two concentric circular coils, one of radius r1 and the other of radius r2 (r1 < r2) placed coaxially with centers coinciding with each other. Obtain the expression for the mutual inductance of the arrangement.


A coil of self-inductance 2.5H and resistance 20Ω is connected to a battery of emf 120V having the internal resistance of 5 n. Find:

1) The time constant of the circuit.

2) The current in the circuit in steady state


Two circular loops are placed with their centres separated by a fixed distance. How would you orient the loops to have (a) the largest mutual inductance (b) the smallest mutual inductance?


Find the mutual inductance between the circular coil and the loop shown in figure.


The current in a long solenoid of radius R and having n turns per unit length is given by i= i0 sin ωt. A coil having N turns is wound around it near the centre. Find (a) the induced emf in the coil and (b) the mutual inductance between the solenoid ant the coil.


A solenoid of length 20 cm, area of cross-section 4.0 cm2 and having 4000 turns is placed inside another solenoid of 2000 turns having a cross-sectional area 8.0 cm2 and  length 10 cm. Find the mutual inductance between the solenoids.


A pair of adjacent coils has a mutual inductance of 1.5 H. If the current in one coil changes from 0 to 10 A in 0.2 s, what is the change of flux linkage with the other coil?


An emf of 96.0 mV is induced in the windings of a coil when the current in a nearby coil is increasing at the rate of 1.20 A/s. What is the mutual inductance (M) of the two coils?


A long solenoid of length l, cross-sectional area A and having N1 turns (primary coil), has a small coil of N2 turns (secondary coil) wound about its center. Determine the Mutual inductance (M) of the two coils.


A pair of the adjacent coil has a mutual inductance of 1.5 H. If the current in one coil varies from 0 to 20 A in 0.5 s, what is the change of flux linked with the other coil. 


Two coils P and Q are kept near each other. When no current flows through coil P and current increases in coil Q at the rate 10 A/s, the e.m.f. in coil P is 20 mV. When coil Q carries no current and current of 1.6 A flows through coil P, the magnetic flux linked with the coil Q is ____________.


The dimensions of self or mutual inductance are given as ______.


In mutual induction, the main current remains same because ____________.


In an induction coil, the coefficient of mutual inductance is 6 henry. If a current of 10 ampere in the primary coil is cut-off in `1/1500"s"`, the e.m.f. at the terminals of the secondary coil will be ____________.


Two different wire loops are concentric and lie in the same plane. The current in the outer loop (I) is clockwise and increases with time. The induced current in the inner loop.


The mutual inductance between two coplanar concentric rings A and B of radii 'R1' and 'R2' placed in air when a current 'I' flows through ring A is (R1 >> R2) (µ0 = permeability of free space) ____________.


Two coils P and Q have mutual inductance 'M' H. If the current in the primary is I = I0 sin `omega`t, then the maximum vlaue of e.m.f. indued in coil Q is ____________.


The coefficient of mutual inductance is 2H and induced e.m.f. across secondary is 2 kV. Current in the primary is reduced from 6 A and 3A. The time required for the change of current is ____________.


The mutual inductance between two coils depends on ______.

Two coils are placed close to each other. The mutual inductance of the pair of coils depends upon the ______.


Two circular coils have their centres at the same point. The mutual inductance between them will be maximum when their axes ______


Two conducting circular loops of radii R1 and R2 are placed in the same plane with their centres coinciding. If R1 > > R2, the mutual inductance M between them will be directly proportional to ______.


Two conducting circular loops of radii R1 and R2 are placed in the same plane with their centres coinciding. If R1 >> R2, the mutual inductance M between them will be directly proportional to ______.


There are two coils A and B seperated by some distance. If a current of 2A flows through A, a magnetic flux of 10-2 Wb passes through B (no current through B). If no current passes through A and a current of 1A passes through B, what is the flux through A?


An emf of 91 mV is induced in the windings of a coil when the current in o nearby coil is increasing at the rate of 1.3 A/s. what is the mutual inductance (M) of the two coils in mH?


A plane loop is shaped in the form as shown in figure with radii a = 20 cm and b = 10 cm and is placed in a uniform time varying magnetic field B = B0 sin ωt, where B0 = 10 mT and ω = 100 rad/s. The amplitude of the current induced in the loop if its resistance per unit length is equal to 50 × 10-3 Ω/m. The inductance of the loop is negligible is ______ A.


A toroid is a long coil of wire wound over a circular core. The major radius and cross-sectional radius of the toroid are R and r, respectively. The coefficient of mutual induction of the toroid is ______.

(The magnetic field in it is uniform, N = number of turns, R >> r, μ0 = permeability of free space)


Two circular loops, one of small radius r and the other of larger radius R, such that R >> r, are placed coaxially with centres coinciding. Obtain the mutual inductance of the arrangement.


State and define the SI unit of mutual inductance.


Two coils having self inductances L1 = 75 mH and L2 = 55 mH are coupled with each other. The coefficient of coupling (K) is 0. 75. Calculate the mutual inductance (M) of the two coils


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×