Questions with the keyword 'energy'

• What will happen if too many people inhabit the Earth eventually and we run out of energy sources? by jamesat79 to Christina, Jess Comments: (So far, one comment )
• If photons are just energy, why are they affected by objects? by desorgherm and 1 other. to Christina, Jess Comments: (No comments so far )
• When civillisation of humans started, how did people create or get energy without any machines? by ritchie007 to Steve Comments: (No comments so far )
• I have heard that cars can run on chocolate, if so, how does that work and how fast would the car be able to go? by rosekverity to Colin Comments: (No comments so far )
• Do you think that there is such thing as a totally renewable energy source? by spacenut1982 to Christina, Colin, Jess, Samaneh, Steve Comments: (So far, one comment )
• What is energy? Can you define it? Also, how do magnets work? One more: is time travel ever possible and why? by 11vinceh and 1 other. to Christina, Colin, Jess, Samaneh, Steve Comments: (so far, 2s comments )