Triangular pulses of light a laser emits triangularupulses of light (? = 905 nm). each pulse has a duration ? -5 ns and contains 1011 photons. the repetition frequency is 10 mhz. question 1: how much radiant energy (in j) does each pulse contain? answer question 2: what is the peak power (in w) of each pulse?question 3: what is the average power (in w) of each pulse? answer question 4: what is the average output power (in w) of the laser?

Diego is trying to lift a piano to the second floor of his house. diego uses a pulley system and gives a big lift to the piano. the piano moves upward, then stops, and then it starts to fall to the ground. which list best describes the forces on the piano in the proper order? positive force → balanced force → negative force negative force → balanced force → positive force positive force → unbalanced force → negative force negative force → unbalanced force → positive force