Suppose that, while lying on a beach near the equator watching the Sun set over a calm ocean. you start a stopwatch just as the top of the Sun disappears. You then stand, elevating your eyes by a height H=1.70 m, and stop the watch when the top of the Sun again disappears. If the elapsed time is t=11.1 s, what is the radius r of Earth?

How much work would a child do while puling a 12-kg wagon a distance of 3m with a 22 n force directed 30 degrees with respect to the horizontal? (a) 82j (b) 52j (c) 109j (d) 95j

1. a camcorder has a power rating of 19 watts. if the output voltage from its battery is 7 volts, what current does it use?answer units 2. a 1.5m wire carries a 6 a current when a potential difference of 57 v is applied. what is the resistance of the wire? yourunits 3. a clothes dryer uses about 2 amps of current from a 240 volt line. how much power does it use? yourunits 4.

Which of the following correctly describes what happens when an atomic bomb explodes? small pieces of fissionable material are joined and form a body with a mass greater than the critical mass, the relative number of neutrons escaping decreases, and a chain reaction and explosion result. large pieces of fissionable matter are brought together quickly and form a body with a mass smaller than the critical mass, the relative number of escaping neutrons increases, and a chain reaction and explosion result.