can you check my answers?
2.is more work required to bring a fully loaded truck up to a given speed, than the same truck lightly loaded? defend your answer?
-more work is required to bring a fully loaded truck up to a given speed because it is doing more work since it is fully loaded.
5. a cart gains energy as it rolls down a hill. what is the force that does the work?
-the force that does the work is the hill.
8. engergy of an object depends on the reference frame of the observer. explain why you agree or disagree? ( This one I don't understand)
10. you and a flight attendant toss a ball back and forth in an airplane flight. does the ke of the ball depend on the speed of the airplane?carfully explain your answer?
-i got that the ke does depend on the speed of the plane because the faster the plane, the faster the ball will go.
13. you watch your friend take off in a jet plane and you comment on the kinetic energy she has acquired. but she says she has no such increse in kinetic enegery. who is correct?
-i got that the friend was correct
I can provide feedback on your answers.
2. Your answer is correct. A fully loaded truck requires more work to bring it up to a given speed because it has a greater mass, and therefore, more force is required to accelerate it compared to a lightly loaded truck.
5. Your answer is partially correct. The force that does the work is actually the force of gravity acting on the cart as it rolls down the hill. This force is responsible for the conversion of potential energy into kinetic energy.
8. The statement suggests that the energy of an object depends on the reference frame of the observer. In this case, I disagree with the statement. The energy of an object does not depend on the reference frame of the observer. Energy is a scalar quantity and is independent of any specific observer. However, the perception of energy may vary depending on the observer's frame of reference.
10. Your answer is partially correct. The kinetic energy of the ball does not directly depend on the speed of the airplane. The speed of the ball depends on the relative motion between the ball and the person throwing it. However, if the plane is moving at a high speed, it may affect the trajectory or apparent motion of the ball due to air resistance or wind inside the airplane.
13. Your answer is incorrect. The correct answer is that you are correct. As the jet plane takes off, it gains kinetic energy due to its increased speed. Your friend may be confused thinking that kinetic energy is not gained, but the fact is that the person in motion (in this case, the plane) does acquire kinetic energy.