Acar of mass 1689 kg collides head-on with a parked truck of mass 2000 kg. spring mounted bumpers ensure that the collision is essentially elastic. if the velocity of the truck is (in the same direction as the car's initial velocity) after the collision, what was the initial speed of the car?

Abird sitting high in a tree is an example of what type of wnergy

When an object is heated it contracts. a. true b. false

Astone is dropped from the upper observation deck of a tower, 250 m above the ground. (assume g = 9.8 m/s2.) (a) find the distance (in meters) of the stone above ground level at time t. h(t) = (b) how long does it take the stone to reach the ground? (round your answer to two decimal places.) s (c) with what velocity does it strike the ground? (round your answer to one decimal place.) m/s (d) if the stone is thrown downward with a speed of 2 m/s, how long does it take to reach the ground? (round your answer to two decimal places.) s