NEET Physics — Magnetic Effects of Current and Magnetism

A circular coil of radius $0.05 \, \text{m}$ with 30 turns carries $2.5 \, \text{A}$. What is the magnetic field at the center? ($\mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A}$)

A long wire carries $20 \, \text{A}$. At what distance from the wire is the magnetic field $4 \times 10^{-6} \, \text{T}$? ($\mu_0 = 4 \pi \times 10^{-7} \, \text{T m/A}$)

A proton moves at $3 \times 10^7 \, \text{m/s}$ perpendicular to a field of $0.1 \, \text{T}$. What is the radius of its path? (Mass = $1.67 \times 10^{-27} \, \text{kg}$, charge = $1.6 \times 10^{-19} \, \text{C}$)

A straight wire of length $0.7 \, \text{m}$ carries a current of $5 \, \text{A}$ perpendicular to a uniform magnetic field of $0.6 \, \text{T}$. What is the force on the wire?

A square loop of side $0.2 \, \text{m}$ with 30 turns carries $1.5 \, \text{A}$ in a magnetic field of $0.4 \, \text{T}$. The plane of the loop is at $60^\circ$ to the field. What is the torque?