Question

A magnet oscillating in a horizontal plane has a time period of 2 seconds at a place where the angle of dip is 30o and 3 seconds at another place where the angle of dip is 60o. The ratio of resultant magnetic fields at the two places is

Answer 1

$\huge\underline\mathfrak{heya}$

the correct answer is

$\frac{t}{ \sqrt{2} }$

Answer 2

Answer:

9/ 4√3

Explanation:

A magnet oscillating in a horizontal plane has a time period of 2 seconds at a place where the angle of dip is 30o and 3 seconds at another place where the angle of dip is 60o. The ratio of resultant magnetic fields at the two places is

Time period is inversely propositional to Bh.

T is proportional to 1 / B √(Cos Ф)

Hence,

T1 / T2 = B2/B1 √ (Cos Ф2/ Cos Ф1)

Hence,

B1 / B2 = (T2/T1)² (cos Ф2/ cos Ф1)

B1 / B2 = (3/2)² ( cos 60/ cos  30)

B1 / B2 = 9/ 4√3