5. A 250 g car at rest rolls down a frictionless incline from a starting height of 0.75 m. What is the final velocity of the car?

If a spring has a k value of 100 newtons per meter and it is stretched 0.50 meters, what is the restoring force of the spring?

Aparticle's position is given by x = 3.00 - 9.00t + 3t2, in which x is in meters and t is in seconds. (a) what is its velocity at t = 1 s? (b) is it moving in the positive or negative direction of x just then? (c) what is its speed just then? (d) is the speed increasing or decreasing just then? (try answering the next two questions without further calculation.) (e) is there ever an instant when the velocity is zero? if so, give the time t; if not, answer "0". (f) is there a time after t = 3 s when the particle is moving in the negative direction of x? if so, give the time t; if not, answer "0".

Daughter element the new element produced along with a decay particle in a nuclear transmutation 2. half-life the substance that decays in a nuclear transmutation 3. parent element the change of one chemical element into another by nuclear decay or radioactive bombardment 4. transmutation the time required for the decay of one-half of the atoms in a sample of radioactive material