Why are skies blue? 1. Oxygen and nitrogen molecules natural color is blue.
2. Oxygen and nitrogen molecules filter out the reds and yellows leaving the shorter blue wavelengths.
3. Oxygen and nitrogen molecules scatters the shorter blue and violet wavelengths throughout the atmosphere giving it a blue color while longer yellows and reds pass through invisibly.

You hang a book bag on a spring scale and place the bag on a platform scale so that the platform scale reads 23.7n and the spring scale reads 13.8n. what is the magnitude of the force that earth exerts on the bag?

Is a volume of space that is empty of matter.

Diego is trying to lift a piano to the second floor of his house. diego uses a pulley system and gives a big lift to the piano. the piano moves upward, then stops, and then it starts to fall to the ground. which list best describes the forces on the piano in the proper order? a. positive force, balanced force, negative force b. negative force, balanced force, positive force c. positive force, unbalanced force, negative force d. negative force, unbalanced force, positive force