The current in a 20 mh inductor is known to be: i = 40 ma for t ≤ 0 i = a1e−10,000t + a2e−40,000t a for t ≥ 0 where t is in seconds. the voltage across the inductor (passive sign convention) is 28 v at t = 0. a) find the correct expression for the voltage across the inductor for t > 0. b) find the time, greater than zero, when the power at the terminals of the inductor is zero.

While goofing off at the ice skating rink, a student takes off her shoes and places each of them on the ice. her friend, a hockey player, then shoots a hockey puck at each shoe. the first puck immediately comes to rest after it collides with the left shoe. the second puck rebounds after it collides with the right shoe. if each hockey puck has the same incoming speed, which shoe has greater speed after the collision? the right shoe. both shoes have the same speed. the left shoe.

More solar radiation is absorbed by earth’s surface than by

The amount of potential energy possessed by an elevated object is equal to what?