Q1. A student holding two weights close to his chest is sitting on a frictionless chair; the student and chair are rotating with an angular speed of 11.7 rad/s. The moment of inertia of Student + Weights + Chair system about an axis of rotation is 21.5 kg.m2. Currently the student extends his arms horizontally to increase the moment of inertia by 0.138 %. Discover the new angular speed of the system.
(Give the answer in three significant figures and SI units)
Q2. A toroidal solenoid has 570 turns, cross-sectional area 7.00, and mean radius 4.70 .Calculate the coil's self-inductance. If the current decreases uniformly from 5.00 to 2.00 in 3.00, estimate the self-induced emf in the coil.