The time period of a freely suspended magnet is 4 s . If it is broken in length into two equal parts and one part is suspended in the same way, then the time period will be

Step-by-step solution

Time period of a suspended magnet is given by T=2 I M B where, I = moment of inertia of the magnet about the point of suspension. M= magnetic moment B= magnetic field When the magnet is broken in length T^ 2^ =2 I^ M^ B T T^ 2^ = I I^ M^ M = mL^2 m^ L^ 2 L^ L Here, m and m ' are the masses of the magnet and L and L's are their lengths. = m m^ L L^ = m m / 2 L L / 2 = 2 2 =2 T^ = T 2 = 4 2 =2 ~s