Welcome to your Chapter 4 Moving Charges and Magnetism MCQs
						 
									 
									
				                        1. 
                        		The magnetic moment of a current I carrying circular coil of radius r and number of turns N varies as 
			
		
	
						 
									
				                        2. 
                        		A current carrying loop is placed in a uniform magnetic field. The torqe acting on it does not depend upon 
			
		
	
						 
									
				                        3. 
                        		A charged particle is moving on circular path with velocity v in a uniform magnetic field B, if the velocity of the charged particle is doubled and strength of magnetic field is halved, then radius becomes 
			
		
	
						 
									
				                        4. 
                        		Two a-particles have the ratio of their velocities as 3 : 2 on entering the field. If they move in different circular paths, then the ratio of the radii of their paths is 
			
		
	
						 
									
				                        5. 
                        		Two charged particles traverse identical helical paths in a completely opposite sense in a uniform magnetic field B =B0k   
			
		
	
						 
									
				                        6. 
                        		A circular coil of radius 4 cm and of 20 turns carries a current of 3 amperes. It is placed in a magnetic field of intensity of 0.5 weber/m². The magnetic dipole moment of the coil is 
			
		
	
						 
									
				                        7. 
                        		An electron is projected with uniform velocity along the axis of a current carrying long solenoid. Which of the following is true? 
			
		
	
						 
									
				                        8. 
                        		In a cyclotron, a charged particle 
			
		
	
						 
									
				                        9. 
                        		If a charged particle moves through a magnetic field perpendicular to it 
			
		
	
						 
									
				                        10. 
                        		A circular current loop of magnetic moment Mis in an arbitrary orientation in an external magnetic field B. The work done to rotate the loop by 30° about an axis perpendicular to its plane is 
			
		
	
						 
									
				                        11. 
                        		The maximum current that can be measured by a galvanometer of resistance 40 Ω is 10 mA. It is converted into voltmeter that can read upto 50 V. The resistance to be connected in the series with the galvanometer is 
			
		
	
						 
									
				                        12. 
                        		What torque acts on a 50 turn coil of 200 cm² area carrying a current of 20 A held with its axis at right angles to a uniform magnetic field of 0.2 T ? 
			
		
	
						 
									
				                        13. 
                        		What is the maximum torque on a rectangular coil of area 4 cm × 80 cm of 400 turns, when carrying a current of 103 A in a magnetic field of 0.2 T? 
			
		
	
						 
									
				                        14. 
                        		Under which of these conditions, the torque acting on the current carrying loop is minimum? 
			
		
	
						 
									
				                        15. 
                        		Identify the factor on which the torque on a planar current loop does not depend. 
			
		
	
						 
									
				                        16. 
                        		Calculate the torque on a 500 turn rectangular coil of length 20 cm and breadth 10 cm, carrying a current of 30 A, when placed making an angle of 60° with a magnetic field of 0.5 T? 
			
		
	
						 
									
				                        17. 
                        		What is the magnetic field inside a pipe? 
			
		
	
						 
									
				                        18. 
                        		The magnetic field due to a current carrying circular loop of radius 4 cm at a point on the axis at a distance of 7 cm from the center is 48 μT. What will be the value at the center of the loop? 
			
		
	
						 
									
				                        19. 
                        		Which of the following particles cannot be accelerated using a cyclotron? 
			
		
	
						 
									
				                        20. 
                        		There are two conductors X and Y carrying a current I and moving in the same direction. p and q are two electron beams also moving in the same direction. Will there be attraction or repulsion between the 2 conductors and between the two electron beams separately?