Define light yearend explain how and why light years are used to measure distances in the universe

Aball bearing at 220.0 °c is dropped into a cup containing 250.0 g of water at 20.0 °c. the water and ball bearing come to a temperature of 30.0 °c. what is the heat capacity of the ball bearing in j/°c? (hint: how are the algebraic signs of q related for the ball bearing and the water? )

Acar is traveling 35 mph on a smooth surface . if a balanced force is applied to the car what happens?

Heating water for hot cocoa while sitting next to a campfire can be examples of conduction, convenction and radiation at the same time agree disagree it depends how you know