Energy is the answer to so many questions. Pull back a spring-powered toy car and rolls forward. Why? Energy. You used your phone all day and it suddenly shut down. Why? No energy. A child eats six ...

In physics, the law of conservation of energy states that the total energy of an isolated system remains constant—it is said to be conserved over time. Energy can be neither created nor be destroyed, ...

Friction is an intrinsic physical phenomenon to curling. Without it, objects in motion would move endlessly, without slowing down. This would cause many safety-related problems: Cars or trains could ...