Consider a wire of a circular cross-section with a radius of r = 3.03 mm. the magnitude of the current density is modeled as j = cr2 = 5.25 ✕ 106 a/m4 r2. what is the current (in a) through the inner section of the wire from the center to r = 0.5r?

Can anybody me with this? ? (picture included.)

A1,700kg car is being used to give a 1,400kg car a push start by exerting a force of 140n the impulse on the smaller car during the 30.0s of contact is +670kg*m/s. what is the impulse of the smaller car on the larger car? -814 kg*m/s 0kg *m/s -670kg*m/s -550kg*m/s

The energy released by a nuclear fusion reaction is produced when