Scientists hypothesize that a large, planet-sized object collided with earth about 4.5 billion years ago and that this impact formed
a. the moon.
b. asteroids.
c. comets.
d. mars.

Amachinist turns the power on to a grinding wheel, at rest, at time t = 0 s. the wheel accelerates uniformly for 10 s and reaches the operating angular velocity of 96 rad/s. the wheel is run at that angular velocity for 40 s and then power is shut off. the wheel slows down uniformly at 1.5 rad/s2 until the wheel stops. in this situation, the time interval of deceleration is closest to:

Which of the following characteristics is fixed, or definite, for all states of matter?

Auniform bridge, 20 m long and weighing 40000 n is supported by two pillars located 3.0 m from each end. if a 19600 n car is parked 8.0 m from one end of the bridge, how much force does each pillar exert?