A red photon in the bright light spectrum of hydrogen gas has an energy of 3.03x10^-19 joule. what energy level transition does an electron in a hydrogen atom undergo to produce this photon?

The mini-refrigerator fire was most likely caused by what type of wiring?

Engineers find a new metal that is stronger than steel but much lighter. this material is also significantly cheaper than what is currently used for most aircraft, available in large quantities, and easy to manufacture. the engineers are excited because this new material will lower the costs of buying and operating airplanes for companies. what is probably the best step for the engineers to make next?

3. a lunar exploration vehicle was created by a research team. it weighs 3,000 kg on the earth. it needs an acceleration of 10 m/s2 on the moon. in order to have the same acceleration, what will be the net force acting on the vehicle on the earth?