NEET Magnetic Effects of Current and Magnetism — Set 11

Question 1

A solenoid with 500 turns per meter carries $ 2 \, \text{A} $. What is the magnetic field inside it? ($ \mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A} $)

Accepted Answer

$ B = \mu_0 n I $. $ B = 4 \pi \times 10^{-7} \times 500 \times 2 = 4 \pi \times 10^{-4} \approx 1.26 \times 10^{-3} \, \text{T} $.

Question 2

Two parallel wires $ 0.07 \, \text{m} $ apart carry $ 8 \, \text{A} $ and $ 6 \, \text{A} $ in the same direction. What is the force per unit length? ($ \mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A} $)

Accepted Answer

$ f = \frac{\mu_0 I_1 I_2}{2 \pi d} $. $ f = \frac{4 \pi \times 10^{-7} \times 8 \times 6}{2 \pi \times 0.07} = \frac{192 \times 10^{-7}}{0.14} = 1.3714 \times 10^{-5} \approx 1.37 \times 10^{-5} \, \text{N/m} $.

Question 3

Two parallel wires $ 0.11 \, \text{m} $ apart carry currents of $ 6 \, \text{A} $ and $ 2 \, \text{A} $ in the same direction. What is the force per unit length between them? ($ \mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A} $)

Accepted Answer

Force per unit length $ f = \frac{\mu_0 I_1 I_2}{2 \pi d} $. $ f = \frac{4 \pi \times 10^{-7} \times 6 \times 2}{2 \pi \times 0.11} = \frac{48 \times 10^{-7}}{0.22} = 2.18 \times 10^{-6} \, \text{N/m} $.

NEET Physics: Magnetic Effects of Current and Magnetism — Practice Set 11

Q1. A solenoid with 500 turns per meter carries \( 2 \, \text{A} \). What is the magnetic field inside it? (\( \mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A} \))

Q2. Two parallel wires \( 0.07 \, \text{m} \) apart carry \( 8 \, \text{A} \) and \( 6 \, \text{A} \) in the same direction. What is the force per unit length? (\( \mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A} \))

Q3. Two parallel wires \( 0.11 \, \text{m} \) apart carry currents of \( 6 \, \text{A} \) and \( 2 \, \text{A} \) in the same direction. What is the force per unit length between them? (\( \mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A} \))

Q4. A rectangular loop of area \( 0.07 \, \text{m}^2 \) with 10 turns carries \( 5 \, \text{A} \) in a field of \( 0.8 \, \text{T} \) perpendicular to the plane. What is the torque?

Q5. A circular loop of radius \( 0.2 \, \text{m} \) with 10 turns carries \( 1.5 \, \text{A} \). What is the magnetic field at its center? (\( \mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A} \))

Q6. A proton moves at \( 2.5 \times 10^7 \, \text{m/s} \) perpendicular to a field of \( 0.15 \, \text{T} \). What is the magnetic force? (Charge = \( 1.6 \times 10^{-19} \, \text{C} \))

Q7. A proton moves at \( 3.5 \times 10^7 \, \text{m/s} \) perpendicular to a field of \( 0.08 \, \text{T} \). What is the radius of its path? (Mass = \( 1.67 \times 10^{-27} \, \text{kg} \), charge = \( 1.6 \times 10^{-19} \, \text{C} \))

Q8. Two parallel wires \( 0.06 \, \text{m} \) apart carry \( 9 \, \text{A} \) and \( 5 \, \text{A} \) in the same direction. What is the force per unit length? (\( \mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A} \))

Q9. A solenoid with 1000 turns per meter carries \( 1.5 \, \text{A} \). What is the magnetic field inside? (\( \mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A} \))

Q10. A circular coil of radius \( 0.11 \, \text{m} \) with 25 turns carries \( 3 \, \text{A} \). What is the magnetic field at the center? (\( \mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A} \))