A ball is thrown from a point distance "a" from a smooth vertical wall against the wall and returns to the point of projection. Prove that the velocity U of
projection and the elevation o of the projection are connected by the
equation.
ite
where e is the coefficient of restitution between the
U? Sin2 oc=ag
(17
ball and the wall.
(05 marks)

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.

Apositive charge moves in the direction of an electric field. which of the following statements are true? check all that apply. check all that apply. 1.the potential energy associated with the charge decreases. 2. the electric field does positive work on the charge. 3. the electric field does negative work on the charge. 4. the potential energy associated with the charge increases. 5. the electric field does not do any work on the charge. 6. the amount of work done on the charge cannot be determined without additional information.

Sort the images based on whether there's a force of attraction or repulsion between the magnets shown. attraction repulsion