Question 1:
easyA length of wire carries a steady current. It is bent first to form a circular plane coil of one turn. The same length is now bent more sharply to give a double loop of smaller radius. The magnetic field at the centre caused by the same current is :
Question 2:
easyConsider two long solenoids \( A \) and \( B \) having length \( 2L \) and \( 3L \) and number of loop as \( N \) and \( 2N \) respectively. If both have same current then ratio of magnetic field inside \( A \) to that of the \( B \) will be
The magnetic field inside a solenoid is given by \( B = \mu_0 \frac{N}{L} I \). Calculating the ratio: \( \frac{B_A}{B_B} = \frac{N_A / L_A}{N_B / L_B} = \frac{N / 2L}{2N / 3L} = \frac{3}{4} \).