Fact 1: Friction causes an object to lose energy.

Fact 2: Friction occurs when surfaces rub together.

Given the two facts above, answer the question "what causes an object to lose energy?" with the following options: 
- high temperature
 - electron transport
 - degrees celcius
 - surfaces rubbing together
 - heat is produced
 - degrees Celsius
 - depress neuronal excitability
 - a tree falling


 

    surfaces rubbing together     