The magnetic needle of a vibration magnetomet | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The frequency of oscillation $n$ of a vibration magnetometer is given by $n = \frac{1}{2 \pi} \sqrt{\frac{M H}{I}}$, which implies $n \propto \sqr

Vedclass · Accepted Answer

$\sqrt{63}$

Vedclass · Answer

(B) The frequency of oscillation $n$ of a vibration magnetometer is given by $n = \frac{1}{2 \pi} \sqrt{\frac{M H}{I}}$, which implies $n \propto \sqrt{B_{net}}$.In the first case, the net magnetic field is $H$. So, $n_1 = 12 \propto \sqrt{H}$.In the second case, the bar magnet is placed along the axis, so the net field is $H + H_1$. Thus, $n_2 = 15 \propto \sqrt{H + H_1}$.Taking the ratio: $\frac{15}{12} = \sqrt{\frac{H + H_1}{H}} \Rightarrow \frac{5}{4} = \sqrt{1 + \frac{H_1}{H}} \Rightarrow \frac{25}{16} = 1 + \frac{H_1}{H} \Rightarrow \frac{H_1}{H} = \frac{9}{16}$.When the poles are interchanged, the field becomes $H - H_1$. Let the new frequency be $n_3$.$\frac{n_3}{n_1} = \sqrt{\frac{H - H_1}{H}} = \sqrt{1 - \frac{H_1}{H}} = \sqrt{1 - \frac{9}{16}} = \sqrt{\frac{7}{16}} = \frac{\sqrt{7}}{4}$.Therefore, $n_3 = 12 	imes \frac{\sqrt{7}}{4} = 3 \sqrt{7} = \sqrt{9 	imes 7} = \sqrt{63}$ oscillations per minute.

Similar Questions

When $2 \ A$ current is passed through a tangent galvanometer,it gives a deflection of $30^\circ$. For $60^\circ$ deflection,the current must be........$A$.

The time period of a magnet is $T$. If it is divided into four equal parts along its axis and perpendicular to its axis as shown,then the time period for each part will be

$A$ magnet is suspended horizontally in the Earth's magnetic field. When it is made to oscillate in a horizontal plane,its time period is $T$. If a wooden block of the same moment of inertia as the magnet is attached to it,what will be the new time period of the system?

The number of turns and radius of cross-section of the coil of a tangent galvanometer are doubled. The reduction factor $K$ will be

Vibration magnetometer is used for comparing

Vedclass Test Series

Exam Paper Generator

Online Exam Module