Can multiple energy sources be applied on one system?

One source of energy was applied to a system and gave a certain output, another source of energy was applied to the same system and a higher output was generated is that possibile? Finally, can you give me some examples of this?

@Shane_B @Jemurray3 @cwrw238 @shadowfiend @ajprincess

Question

Can multiple energy sources be applied on one system? 

One source of energy was applied to a system and gave a certain output, another source of energy was applied to the same system and a higher output was generated is that possibile? Finally, can you give me some examples of this? 

@Shane_B  @Jemurray3 @cwrw238  @shadowfiend  @ajprincess

anonymous · Answer

Thanks for the help in advance!

shane_b · Answer

Not only is it possible...it's more common for a system to obtain energy from multiple sources.  Very seldom is a system completely isolated from all but 1 source of energy...except in phyics/chemistry problems :)

anonymous · Answer

Thanks @Shane_B  I loved how you answered in an optimistic manner!

shane_b · Answer

Thanks :)  I think the reality is that it would be impossible to isolate a system completely from all outside energy forces...or even all but 1.