1. true or false: not every lightning strike produces thunder. 2. for a negative polarity lightning strike, in which direction does the stepped leader travel (upward or downward)? 3. why is lightning most common in florida? 4. true or false: if you are about to be struck by lightning, your hair might stand on end. 5. true or false: lightning can sometimes occur on hot and humid summer evenings when there are no thunderstorms. 6. if you see a flash of lightning and hear thunder 10 seconds later, how far is the lightning from you? 7. true or false: if you touch someone who has been struck by lightning, you might get electrocuted. 8. in a typical thunderstorm, positive charge builds at the top of the cloud. why? 9. if you are in an open area with no nearby shelter, and you feel as though you are about to be struck by lightning, what should you do? 10. how many times per second do lightning strikes happen on earth?

Which statement is true for light passing into a medium that is more optically dense than the first medium through which it past

Aball is thrown upward. at a height of 10 meters above the ground, the ball has a potential energy of 50 joules (with the potential energy equal to zero at ground level) and is moving upward with a kinetic energy of 50 joules. what is the maximum height h reached by the ball? consider air friction to be negligible. 1. h ≈ 10 m 2. h ≈ 50 m 3. h ≈ 30 m 4. h ≈ 40 m 5. h ≈ 20 m 003 10.0 points which of the two object shown below has the greatest kinetic energy? a m b 1 2 m v 2v 1. kinetic energies are the same. 2. a 3. b 4. unable to determine. 004 10.0 points tim, with mass 74.6 kg, climbs a gymnasium rope a distance of 3.1 m. the acceleration of gravity is 9.8 m/s 2 . how much potential energy does tim gain? answer in units of j. 005 10.0 points a car is moving at 64 miles per hour. the kinetic energy of that car is 5 × 105 j. how much energy does the same car have when it moves at 111 miles per hour? answer in units of j. 006 10.0 points an 102 kg man climbs up a 1 m high flight of stairs. the acceleration of gravity is 9.81 m/s 2 . w

The heliocentric and the geocentric models of the solar system included these central principles