Concepts Of Physics MCQ Edition [Volume 2]PhysicsElectromagnetic Induction
A rectangular wire frame abcd has dimensions 32 cm 8.0 cm and a total resistance of 2.0 . By applying a force of 3.2 10⁻⁵ N , it is pulled out of a magnetic field B = 0.020 T as shown in the figure. It is observed that the frame travels with a constant speed. Determine the potential difference between the points c and d .
Options
- A4.0 10⁻³ V
- B4.0 10⁻² V
- C8.0 10⁻³ V
- D3.6 10⁻² V
Correct answer
B. 4.0 10⁻² V
Step-by-step solution
Given: Dimensions of the rectangular frame = 32 cm 8.0 cm Total resistance of the frame, R = 2.0 Applied force, F = 3.2 10⁻⁵ N Magnetic field, B = 0.020 T The total perimeter of the frame is: p = 2 (32 + 8.0) = 80 cm = 0.8 m Let the length of the side ab (and cd ) be l . Since the frame is pulled out of the magnetic field with a constant speed, the net force on it is zero. The applied force F is balanced by the magnetic force acting on the current-carrying side ab (which is inside the magnetic field). F = I l B I =