Moving Charges and Magnetism-Quiz-4

MOVING CHARGES AND MAGNETISM

Dear Readers,

JEE Advanced Physics Syllabus can be referred by the IIT aspirants to get a detailed list of all topics that are important in cracking the entrance examination. JEE Advanced syllabus for Physics has been designed in such a way that it offers very practical and application-based learning to further make it easier for students to understand every concept or topic by correlating it with day-to-day experiences. In comparison to the other two subjects, the syllabus of JEE Advanced for physics is developed in such a way so as to test the deep understanding and application of concepts.

Q1. The resistances of three parts of a circular loop are as shown in figure. The magnetic field at the centre O is (current enters at A and leaves at B and C as shown)

•  (μ_0 I)/6a
•  (μ_0 I)/3a
•  2/3 (μ_0 I)/a
•  zero

Solution

Q2.A wire of length ‘l’ is used to form a coil. The magnetic field at its centre for a given current in it is minimum if the coil has

•  4 turns
•  2 turns
•  1 turns
•  Data is not sufficient

Solution

Q3.  A beam of mixture of α particles and protons are accelerated through same potential difference before entering into the magnitude field of strengthB. If r1=5 cm, then r2 is

•  5cm
•  5√2 cm
•  10√2 cm
•  20cm

Solution

Q4. A uniform magnetic field exists in a region which forms an equilateral triangle of side a. The magnetic field is perpendicular to the plane of the triangle. A charge q enters into this magnetic field perpendicular to a side with speed v. The charge enters from midpoint and leaves the field from mid-point of other side. Magnetic induction in the triangle is

•  mv/qa
•  2mv/qa
•  mv/2qa
•  mv/4qa

Solution

Q5. A Q5.A magnetic field B ⃗=B_0 j ̂ exists in the region a<x<2a and B ⃗=-B_0 j ̂, in the region 2a<x<3a, where B_0 is a positive constant. A positive point charge moving with a velocity V ⃗=V_0 i ̂, where V_0 is a positive constant, enters the magnetic field at x=a. The trajectory of the charge in this region can be like

 

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Q6. An infinitely long hollow conducting cylinder with inner radius R/2 and outer radius R carries a uniform current density along its length. The magnitude of the magnetic field |B ⃗| as a function of the radial distance r from the axis is best represented by

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Solution

Q7.Three particles, an electron (e), a proton (p) and helium, atom (He) are moving in circular paths with constant speeds in the x-y plane in a region where a uniform magnetic field B exists along z-axis. The times taken by e, p and He inside the field to complete one revolution are t_e,t_p and t_He respectively Then,

•  t_He>t_p=t_e
•  t_He>t_p>t_e
•  t_He=t_p=t_e
•  None of these

Solution

Q8.A charged particle is whirled in a horizontal circle on a frictionless table by attaching it to a string fixed at one end. If a magnetic field is switched on in the vertical direction, the tension in the string

•  Will increase
•  TWill decrease
•  Remains same
•  May increase or decrease

Solution

Q9.Two particles X and Y having equal charges, after being accelerated through the same potential difference, enter a region of uniform magnetic field and describe circular paths of radii R_1 and R_2, respectively. The ratio of the mass of X to that of Y is

•  (R_1/R_2 )^(1/2)
•  R_2/R_1
•  (R_1/R_2 )^2
•  R_1/R_2

Solution

Q10. The plane of a rectangular loop of wire sides 0.05 m and 0.08 m is parallel to a uniform magnetic field of induction 1.5 ×10^(-2) T. A current of 10.0 ampere flows through the loop. If the side of length 0.08m is normal and the side of length 0.05m is parallel to the lines of induction, then the torque acting on the loop is

•  6000 Nm
•  zero
•  1.2×10^(-2)Nm
• 6×10^(-4)Nm

Solution