Question: You are in a car with some helium balloons and hit the gas. While you accelerate, which way does the balloon move?
Answer: It moves forward towards the front of the car, even though you are forced backwards. The helium balloon is less dense than the air so when you accelerate the air in the car will move backwards compared to the balloon pushing the balloon forward because the balloon is lighter.
Question: One day a man broke his leg. When he was sent home from the hospital he had to use a wheelchair. The doctors told him he could not go up stairs. When the man got home he realized he had stairs to get into his house on both sides. The man saw his neighbor, the doctor who x-rayed him at the hospital, getting out or her car. The man asked "can you carry me up the stairs?" The woman replied "no." Why?
Answer: She told the man he could not go up stairs