What would most likely cause the future acceleration of the expansion of the universe?
radiation from the Sun
the existence of background radiation
the continued existence of dark energy
light shifts identified by the Doppler effect

Two friends are having a conversation. anna says a satellite in orbit is in freefall because the satellite keeps falling toward earth. tom says a satellite in orbit is not in freefall because the acceleration due to gravity is not 9.80 m/2 . who do you agree with and why?

To travel at constant speed, a car engine provides 24kw of useful power. the driving force on the car is 600n. at what speed does it travel?

Give an example in which the electrical energy changes to light energy