A train that was originally going 200 mph slows down to a stop at a train crossing. Explain what happened to the kinetic energy of the car as it slowed down.
The kinetic energy of the train remained the same, because kinetic energy does not relate to speed.
The kinetic energy of the train remained the same, because the train's mass remained the same.
The kinetic energy of the train decreased, because the speed of the train decreased.
The kinetic energy of the train increased, because the speed of the train increased.

What is special about a dc circuit ?

Which missing item would complete this alpha decay reaction ? > 228/88ra + 4/2he a.224/96 rn b. 232/90 th c. 230/92 u d. 235/92 u

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