A compass needle of oscillation magnetometer oscillates 20 times per minute at a place P of dip $30^{\circ}$ The number of oscillations per minute become 10 at another place Q of $60^{\circ}$ dip. The ratio of the total magnetic field at the two places $\left(\mathrm{B}_{\mathrm{Q}}: \mathrm{B}_{\mathrm{P}}\right)$ is :
Hello 👋 Welcome to Competishun – India’s most trusted platform for JEE & NEET preparation. Need help with JEE / NEET courses, fees, batches, test series or free study material? Chat with us now 👇