7. The uranium nucleus contains a charge 92 times that of the proton. If a proton is shot at the nucleus, how large a repulsive force does the proton experience due to the nucleus when it is 1×10-11m from the nucleus? a) 1.1 ×10-4N b) 2.1 ×10-4N c) 1.1 ×10-2N d) 2.1 ×10-2N

While goofing off at the ice skating rink, a student takes off her shoes and places each of them on the ice. her friend, a hockey player, then shoots a hockey puck at each shoe. the first puck immediately comes to rest after it collides with the left shoe. the second puck rebounds after it collides with the right shoe. if each hockey puck has the same incoming speed, which shoe has greater speed after the collision? the right shoe. both shoes have the same speed. the left shoe.

20. threshold braking in the vehicle's braking system occurs when a. the brake pedal is pushed, heel on floorboard, with full foot pressure. b. the brakes are exerting full braking power, without traction loss. c. the driver begins pushing down the brake pedal, with moderate slowdown. d. the brakes just begin to take hold with a gradual slowdown.

The frequency of the fundamental of the guitar string is 320 hz. at what speed v do waves move along that string?