Question

3R MC 12 Two identical solenoids are connected to each other so that they carry the same current, and are inserted through two loops in an electrical circuit, as shown left diagram. The solenoids are oriented such that when you loolk from one end, the currents are circulating in opposite directions, as showin in the second diagram. For a period of time, the current flowing through the solenoids is changing in a steady linear manner: It) ~ t. During this time the current measured in ammeter Al is a constanI What is the value of AI 2R the current flowing through ammeter A2 during this time? A2 reads a current Io a. b. A2 reads a current 21/3 c. A2 reads a current 310/2 d. A2 reads a current 31 e. A2 reads a current 4I AS 5 A conducting bar of length L = 55cm slides friction!essly along a conducting rail that lies in a plane perpendicular to a magnetic field, as shown in the diagram The bar is made to slide in the - direction at a constant velocity of v3.2mls The magnetic field is not uniform, and it grows stronger as a function of r according to B(x)-ax, a 085 im At the moment depicted in the diagram, the bar is at position 80cm Find the voltage drop across the lightbulb when the bar is at the position shown in the diagram. Include in your answer the side (right or left) of the lightbulb that is at higher voltage. Assume that the bar and rails have no resistance a. One Possible Solution There is a potential difference induced between the ends of the bar as a result of motional emf, and this potential difference drives a curent through the lightbulb. The RHR for magnetic force on charges tells us that the positive chargesll be driven downward in the bar, which means that the bottom of the bar is at higher potential, and the current driven through the lightbulb will be to the right. The amount of voltage difference is simply Emotional BvL-ax vL-0.85(0.8m)3.2(055m) 0.96v b. At the moment when the bar is at the position shown in the diagram, the force exerted on it to keep it moving at a constant speed is 15N. Find the resistance of the lightbulb One Possible Solution The force applied to the bar equals the force exerted on it by the magnetic field. This allows us to calculate the current flowing through the bar (note that the bar is at right angles to the field) 15N LB Lax (055m) 0.85(0.8m) Now that we have the current through and the voltage drop across the lightbulb, we can compute its resistance -0.0192 I 50A [Hint: The power delivered to a moving object by a force can be computed directly from the force on the object and its velocity.]

Answer 1

MC12: AS5: I see you already have the solution. please let me know if you need me to redo this?

3R A1 i0o In the loop abcda using loop law 3 3Rio-2R1 = 0, therefore i =-10 2R So option C is correct