Physics Quiz....very Urgent!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 1.As a rocket rises its acceleration increases. Why does this happen? (assume that the acceleration due to gravity and air resistance are nearly constant during the ascent) 2. If the head of the hammer is loose, and you wish tighten it by baging it against the top of a work benchm why si it bettwee to hold it with the handle down ( as indicated in the diagram to the right) than to hold with the head down? 3. If a four-engine jet accelerate down a runway at 2.0m/s^2 and one of its engines suddenly fails, how much acceleration will the ramaining three produce? ( asuume that all four engines are identical.) 4. If an elephant was chasing you, its enourmous mass would be most threatning, but if made a quick turn, its mass would be to your advantage. Why? 5. Many automobile passengers waiting at traffic lights have suffered nech injuries when their cars were struck from behind. Explain why this happens, how can head rests reduce the severity of this type of injury? 6. Some people used to think that a spaceship could not maneuver over it left the earths's atmosphere because it would have no air to push against, obiviously, this thinking must be wrong since rocket engines have been used to steer vehicles through space since the late 1950s. how does a rocket engine manage to apply a force to a spaceship in the vacuum of outer space? 7. If a bicycle and a truck have a head-on collision, which vehicle experiences the greater force? which undergoes the greater accleration? 8.two closed containers look the same, but one is tightly packed with lead and the other loosely packed with feathers. how could you determine which was which if you and the containers were weightless in outer space? 9. Two teams are involved in a tug-of-war. why is it wrong to say that the team that pulls the hardest wins? what force reallly determines who wins? 10. The photo on the website shows a physics teacher sandwiche between two bed of nails. A second physics teacher is pulverizing a cement block on top of the upper bed with a sledgehammer. If the cement block were replaced with a smaller brick, would the demonstration be more or less safe?