Moving Charges and Magnetism-Quiz-10

MOVING CHARGES AND MAGNETISM-10

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. If the magnetic field at ‘P’ can be written as K tan⁡(α/2), then K is

•    (μ0 I)/4πd
•   (μ0 I)/2πd
•   (μ0 I)/πd
•   (2μ0 I)/πd

Solution

Q2.A charged particle moves insides a pipe which is bent as shown in Figure. If R<mv/qB, then force exerted by the pipe on changed particle at P is (Neglect gravity)

•   Towards centre
  
  
  
  
•   Away from centre
  
  
  
  
•   zero
  
  
  
  
•   none of these
  
  
  
  

Solution

Q3.  Equal currents i=1 A are flowing through the wires parallel to y-axis located at x=+1 m, x=+2 m, x=4 m and so on …, etc. but in opposite directions as shown in figure. The magnetic field (in tesla) at origin would be 

•   -1.33×10^(-7) k ̂
•    1.33×10^(-7) k ̂
•    2.67×10^(-7) k ̂
•    -2.67×10^(-7) k ̂

Solution

Q4. A conducting rod of mass and length l is placed over a smooth horizontal surface. A uniform magnetic field B is acting perpendicular to the rod. Charge q is suddenly passed through the rod and it acquires in initial velocity v on the surface, then q is equal to

•   2mv/Bl
•   Bl/2mv
•   mv/Bl
•   Blv/2m

Solution

Q5.  An infinitely long conductor PQR is bent to form a right angle as shown in figure. A current I flows through PQR. The magnetic field due to this current carrying conductor at the point M is B_1. Now, another infinitely long straight conductor QS, is connected at Q so that the current is 1/2 I in QR as well asa in QS, the current in PQ remaining uncharged. The magnetic filed at M is now B_2. The ratio B_1/B_2 is given by

 

•  1/2
•  1
•  2/3
•  2

Solution
 

Q6. In the plane mirror, the coordinates of images of a charged particle (initially at origin as shown in Figure) after two and a half time periods are (initial velocity of charge particle is V_0 in the xy plane and the plane mirror is perpendicular to0 the x-axis. A uniform magnetic field Bi ̂ exists in the space. P_0 is pitch of helix, R_0 is radius of helix.)

•  17 P_0,0,-2R_0
•   3P_0,0,-2R_0
• 17.5P_0,0,-2R_0
•  3P_0,0,2R_0

Solution

Q7.A charged particle beings to move from the origin in a region which has a uniform magnitude field in the x-direction and a uniform electric field in the y-direction. Its speed is v when it reaches the point(x,y,z). Then, v will depend

•   Only on x
•   Only on y
•  On both x and y, but not z
•   On x,y and z

Solution

Q8.An electron is launched with velocity v vector in a uniform magnetic field B vector. The angle θ between v and B lies between 0 and π/2. Its velocity vector v vector returns to its initial value in a time interval of

•   2πm/eBAlong positive y-axis
•   (2×2πm)/eB
•  πm/eB
•  Depends upon angle between v vector and B vector

Solution

Q9.Two metal strips of length leach are placed parallel to each other in contact with an electric circuit as shown in Fig. The entire in which uniform magnetic field is existing in vertical direction The distance travelled by the wire as a function of time is best given by 1/2×EBb/Rm×t^2 for t<t_0 and l+EBb/Rm(t-t_0) for t≥t_0

•   l+EBb/Rm(t-t_0) for t≥t_0
•  1/2×EBb/Rm×t^2 for all t
•  1/2×EBb/Rm×t^2 for t≤t_0 and then the wire stops
•  1/2×EBb/Rm×t^2 for t≤t_0 and l+E3b/Rm×t for t>t_0 Where t_0=√((2 lmR)/EBb)

Solution

Q10. A current I flows along the length of an infinitely long, straight, thin walled pipe. Then

•   ̂The magnetic field at all points inside the pipe is same, but not zero
•  The magnetic field at any point inside the pipe is zero
•  The magnetic field is zero only on the axis of the pipe
• The magnetic field is different at different points inside the pipe

Solution