Multiple-concept example 5 discusses the principles used in this problem. a neodymium-glass laser emits short pulses of high-intensity electromagnetic waves. the electric field of such a wave has an rms value of erms = 2.0 × 109 n/c. find the average power of each pulse that passes through a 1.6 × 10−5-m2 surface that is perpendicular to the laser beam.

In positive numbers less than 1, the zeros between the decimal point and non zero are significant

Compare the horizontal displacement of the two balls as they travel to the ground. what do you observe?

Aparticle's position is given by x = 3.00 - 9.00t + 3t2, in which x is in meters and t is in seconds. (a) what is its velocity at t = 1 s? (b) is it moving in the positive or negative direction of x just then? (c) what is its speed just then? (d) is the speed increasing or decreasing just then? (try answering the next two questions without further calculation.) (e) is there ever an instant when the velocity is zero? if so, give the time t; if not, answer "0". (f) is there a time after t = 3 s when the particle is moving in the negative direction of x? if so, give the time t; if not, answer "0".