A flight attendant pushes a cart down the aisle of a plane in flight. In determining the acceleration of the cart relative to the plane, which factor do you not need to consider?
- The friction of the cart’s wheels.
- The force with which the flight attendant’s feet push on the floor.
- The velocity of the plane.
- The mass of the items in the cart.
This is College Physics Answers with Shaun Dychko. A flight attendant pushes a cart down the aisle of a plane and we have to determine the acceleration of the cart compared to the plane. What factor do we not need to consider? Well, the friction of the cart's wheels clearly will be important because that's going to have a force in the opposite direction to that which the attendant is applying. The force was the flight attendant's feet push on the floor is relevant because then the floor in turn pushes on the flight attendant to there and turn to point applies the force on the cart. Yes, that's important. The mass of items in the cart is important because the acceleration was related to mass because that's it's inversely proportional to mass. It's going to be the net force divided by mass, this is Newton's second law rearranged. So mass is important. The answer to our question is see the velocity of the plane is not important.