4. a 3.0-kg block slides on a frictionless 20° inclined plane. a force of 16 n acting parallel to the incline and up
the incline is applied to the block. what is the acceleration of the block?
a. 2.0 m/s2 down the incline
b. 5.3 m/s2 up the incline
c. 2.0 m/s- up the incline
d. 3.9 m/s² down the incline
e. 3.9 m/s2 up the incline

If you were to drop a rock from a tall building, assuming that it had not yet hit the ground, and neglecting air resistance. what is its vertical displacement (in m) after 6 s?

Jessie ran 5000 meters from the cops and an average speed of 6 meters / second before he got caught . how long did he run?

Consider an ordinary, helium-filled party balloon with a volume of 2.2 ft3. the lifting force on the balloon due to the outside air is the net resultant of the pressure distribution exerted on the exterior surface of the balloon. using this fact, we can derive archimedes’ principle, namely that the upward force on the balloon is equal to the weight of the air displaced by the balloon. assuming that the balloon is at sea level, where the air density is 0.002377 slug/ft3, calculate the maximum weight that can be lifted by the balloon. note: the molecular weight of air is 28.8 and that of helium is 4.