Question

Three people, John, Paul, and George, stand on top of Garage A to carry out a physics experiment by tossing tennis balls off the top level. All three throw the tennis balls with the same speed, but in different directions. John throws his ball 50 degrees above the horizontal, Paul throws his horizontally, and George throws his 20 degrees below the horizontal. Which of the following statements are true? Select all that are true. Paul's ball lands last.All three hit the ground at the same time. George's ball lands last. All three land the same distance from the base of the garage. John's ball lands last. All three hit the ground traveling at the same speed. All three have the same total energy.

Answer 1

1) John's ball lands last.

2) All three have the same total energy

Step-by-step explanation:

John's ball will land last because his ball was projected at the largest angle. This means that the ball will spend more time in the air when compared to the other balls.

The total energy in a projected particle is the sum of its kinetic energy (0.5mv^2) and its potential energy due to its height (mgh). The total kinetic energy can be as a result of both, or at times fully transformed to either of the energy. For example, at the maximum height, the kinetic energy of John's ball is zero and is fully transformed into potential energy due to that height, whereas George's ball will mostly posses kinetic energy and a little potential energy. The three ball are assumed to have the same properties and are projected with the same initial velocity. This means that they all have the same kinetic energy at the instance of projection which can then be transformed into potential energy, or maintained as a combination of both throughout the flight or simply transformed into potential energy, but the total energy is always conserved.