Aproton accelarates from rest in a unifrom electric field of 630 n/c. at some later time, it's speed is 1.3 * 10^6 m/s. a) find the magnitude of the acceleration of the proton. b) how long does it take the proton to reach this speed? c) how far has it moved in that interval?

The of a machine determines its "usefulness." a. input force b. output force c. mechanical advantage

In an old-fashioned amusement park ride, passengers stand inside a 3.0-m-tall, 5.0-m-diameter hollow steel cylinder with their backs against the wall. the cylinder begins to rotate about a vertical axis. then the floor on which the passengers are standing suddenly drops away! if all goes well, the passengers will “stick” to the wall and not slide. clothing has a static coefficient of friction against steel in the range 0.60 to 1.0 and a kinetic coefficient in the range 0.40 to 0.70. part a what is the minimum rotational frequency, in rpm, for which the ride is safe? express your answer using two significant figures. f f = rpm

When a pendulum is held high and taut and then is released, the pendulum begins to swing. what’s the correct order of the energy transformations in this example? (pe stands for potential energy.)