A battery is connected between two points `A and B` on the circumference of a uniform conducting ring of radius `r` and resistance `R` . One of the arcs `AB` of the ring subtends an angle `theta` at the centre . The value of the magnetic induction at the centre due to the current in the ring isA. proportional to `2(180^(@)-theta)`B. Inversely proportional to `r`C. zero only if `theta=180^(@)`D. zero for all values of `theta`

A battery is connected between two points `A and B` on the circumferen

1.	A battery is connected between two points `A and B` on the circumference of a uniform conducting ring of radius `r` and resistance `R` . One of the arcs `AB` of the ring subtends an angle `theta` at the centre . The value of the magnetic induction at the centre due to the current in the ring isA. proportional to `2(180^(@)-theta)`B. Inversely proportional to `r`C. zero only if `theta=180^(@)`D. zero for all values of `theta`
Answer» Correct Answer - D `b_(1)=(mu_(0)I)/(2R)xx(2pi-theta)/(2pi),B_(2)=(mu_(0)I_(2))/(2R)xx(theta)/(2pi)` But `I_(1)(rho(Rtheta))/(A)=I_(2)(rhoR(2pi-theta))/(A)` `impliesI_(1)theta=I_(2)(2pi-theta)jimpliesB_(1)=B_(2)` But direction of `vec(B)_(1)` and `vec(B)_(2)` are opposite so net magnetic field at the centre is zero.

Discussion

No Comment Found

Related InterviewSolutions

When a current carrying coil is situated in a uniform magnetic field with its magnetic moment antiparallel to the field `i)` Torque on it is maximum `ii)` Torque on it is minimum `iii) PE` of loop is maximum `iv)PE` of loop is minimumA. only `i` and `ii` are trueB. only `ii` and `iii` are trueC. only `iii` and `iv ` are trueD. only `I,ii` and `iii` are true
If plane of coil and uniform magnetic field B(4T0 is same then torque on the current carrying coil is A. `l(piR^(2)) 4(1)`B. `(l(pi R^(2))4)/(2)`C. `(lpi R^(2)4)/(8)`D. Zero
A moving coil type of galvanometer is based upon the principle thatA. a coil carrying current experiences a torque in magnetic field.B. a coil carrying current produces a magnetic field.C. a coil carrying current experiences impulse in a magnetic field.D. a coil carrying current experience a force in magnetic field.
When a current carrying coil is placed in a uniform magnetic field of induction `B`, then a torque `tau` acts on it. If `I` is the current, `n` is the number of turns and `A` is the face area of the coil and the normal to the coil makes an angle `theta` with `B`, ThenA. `tau=BInA`B. `tau = B I nA sin theta`C. `tau=B InA cos theta`D. `tau=B I n A tan theta`
A proton is accelerating on a cyclotron having oscillating frequency of 11 MHz in external magnetic field of 1 T. If the radius of its dees is 55 cm, then its kinetic energy (in MeV) is is `(m_(p)=1.67xx10^(-27)kg, e=1.6xx10^(-19)C)``A. 13.36B. 12.52C. 14.89D. 14.49
A steady current `i` flows in a small square lopp of wire of side `L` in a horizontal plane. The loop is now folded about its middle such that half of it lies in a vertical plane. Let `vecmu_(1)` and `vecmu_(2)` respectively denote the magnetic moments due to the current loop before and after folding. ThenA. `vec(mu_(2))=0`B. `vec(mu_(1))` and `vec(mu_(2))` are in the same directionC. `|vec(mu_(1))|//|vec(mu_(2))|=sqrt(2)`D. `|vec(mu_(1))|//|vec(mu_(2))|=(1//sqrt(2))`
Two positive charges `q_1 and q_2` are moving with velocities `v_1 and v_2` when they are at points A and B, respectively, as shown in Fig. The magnetic force experienced by charge `q_1 ` due to the other charge `q_2` is A. `(mu_(0)q_(1)q_(2)upsilon_(1)upsilon_(2))/(8sqrt(2)pi a^(2))`B. `(mu_(0)q_(1)q_(2)upsilon_(1)upsilon_(2))/(4sqrt(2)pi a^(2))`C. `(mu_(0)q_(1)q_(2)upsilon_(1)upsilon_(2))/(2sqrt(2)pi a^(2))`D. `(mu_(0)q_(1)q_(2)upsilon_(1)upsilon_(2))/(sqrt(2)pi a^(2))`
A particle of mass `m` and charge `q` moves with a constant velocity `v` along the positive `x` direction. It enters a region containing a uniform magnetic field `B` directed along the negative `z` direction, extending from `x = a` to `x = b`. The minimum value of `v` required so that the particle can just enter the region `x gt b` isA. `qb" "B//m`B. `q(b-a)B//m`C. `qa" "B//m`D. `q(b+a)B//2m`
A proton moving with a velocity of `2xx10^(6)ms^(-1)` describes circle of radius `R` in a magnetic field. The speed of an `alpha-` particle to describe a circle of same radius in the same magnitude field isA. `1xx10^(6)m//s`B. `2xx10^(6)m//s`C. `4xx10^(6)m//s`D. `8xx10^(6)m//s`
An electron of energy 1800 eV describes a circular path in magnetic field of flux density 0.4 T. The radius of path is `(q = 1.6 xx 10^(-19) C, m_(e)=9.1 xx 10^(-31) kg)`A. `2.58xx10^(-4)m`B. `3.58xx10^(-4)m`C. `2.58xx10^(-3)m`D. `3.58xx10^(-4)m`

Discussion

No Comment Found

Related InterviewSolutions

Reply to Comment