16. Why does the number of carts matter when designing a roller coaster track? (Hint: PE = mass x gravity x height and KE = /2 mass x velocity ^2) Choose 2 correct statements.

A. Adding carts increases the mass and decreases the total energy in the system.

B. Adding carts increases the mass and increases the total energy in the system.

C. Removing carts increases the mass and decreases the total energy in the system.

D. Removing carts decreases the mass and decreases the total energy in the system.

What is the coefficient of kinetic friction μk between the block and the tabletop?

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

Water flows through a garden hose which is attached to a nozzle. the water flows through hose with a speed of 2.19 m/s and through the nozzle with a speed of 19.8 m/s. calculate the maximum height (in m) to which water could be squirted if it emerges from the nozzle and emerges with the nozzle removed.