A toroid is a solenoid in the shape of a donut (Fig. 20-60). Use Ampére's law along the circular paths, shown dashed in Fig 20-60a, to determine that the magnetic field a) inside the toroid is B= u0 NI/2piR where N is the total number of turns and...
b)outside the toroid is B=0
c)If not, how does it vary?

When the force acting on an object points at least partially in the direction of the motion the work done is considered to be negative

How are positive ions different from neutral atoms

Aball is thrown from the top of a building with an initial velocity of 21.9 m/s straight upward, at an initial height of 51.6 m above the ground. the ball just misses the edge of the roof on its way down, as shown in the figure. (a) determine the time needed for the ball to reach its maximum height. (b) determine the maximum height. (c) determine the time needed for the ball to return to the height from which it was thrown, and the velocity of the ball at that instant. (d) determine the time needed for the ball to reach the ground. (e) determine the velocity and position of the ball at t = 5.35 s.