While in canada, the engineer buys a new electric toothbrush. when she returns home she designs another
transformer so she can use the toothbrush in india. this transformer also has an input coil with 240 turns.
how many turns should the output coil have?

Electric charge is uniformly distributed inside a nonconducting sphere of radius 0.30 m. the electric field at a point p, which is 0.50 m from the center of the sphere, is 15,000 n/c and is directed radially outward. what is the maximum magnitude of the electric field due to this sphere

Scientists use laser range-finding to measure the distance to the moon with great accuracy. a brief laser pulse is fired at the moon, then the time interval is measured until the "echo" is seen by a telescope. a laser beam spreads out as it travels because it diffracts through a circular exit as it leaves the laser. in order for the reflected light to be bright enough to detect, the laser spot on the moon must be no more than 1.0 km in diameter. staying within this diameter is accomplished by using a special large-diameter laser. part a if λ = 540nm , what is the minimum diameter of the circular opening from which the laser beam emerges? the earth-moon distance is 384,000 km. express your answer to two significant figures and include the appropriate units.

Ten students stand in a circle and are told to make a transverse wave. what best describes the motion of the students? each student bumps the shoulder of his or her neighbor. at the exact time, all students take a step to the right. the students skip clockwise, going in a circular motion. one at a time, each student lifts his or her hands up and then down.