1. Describe the motion of a freely falling bodies. 2. A ball is thrown vertically upward with a velocity of \( 20 \mathrm{~m} / \mathrm{s} \) from the top of a building. The height of the point from where the ball is thrown is 25 m from the ground. (a) how high will the ball rise? (b) how long will it take for the ball to hit the ground? 3. A ball is dropped on the floor from a height of 10 m . It rebounds to a height of 2.5 m . If the ball is in contact with the floor for 0.01 sec , what is the average acceleration during contact? 4. If a stone is thrown vertically downward into a well with a speed of \( 10 \mathrm{~m} / \mathrm{s} \), how long will it take it to reach the water surface 60 m below?

Una pesante maniglia in ottone ha una massa di \( 3,40 \mathrm{~kg} \). Quale volume in \( \mathrm{cm}^{3} \) occupa la maniglia? La densità dell'ottone è \( 8,40 \cdot 10^{3} \mathrm{~kg} / \mathrm{m}^{3} \).

What will happen to the speed of a ball after it is thrown upward into the air? \( \begin{array}{ll}\text { A. Increnses } & \text { C. increases and then d }\end{array} \)

Sloths are known for being slow. An average tree sloth moves at a speed of \( 0.743 \mathrm{~m} / \mathrm{s} \). T the nearest second, how long does it take a sloth to travel 22.3 m at this speed?

Dados los vectores \( \vec{P}=(1 \hat{i}-2 \hat{j}) m \) y \( \vec{Q}=(-9 \hat{i}+20 \hat{j}) m \), el vector resultante de la suma \( \vec{P}+\vec{Q} \) es:

What is the dot product of vector \( j \) with a magnitude of 4 and a direction of \( 30^{\circ} \) and vector k with a magnitude of 10 and a direction of \( 15^{\circ} \) ? (Round your answer to the nearest tenth.)