Are all of these examples of activation energy? If not which ones aren't.
1.To go forward on your bicycle, you must paddle.
2. A wind gust knocks a chimney brick to the ground.
3. Sound vibrations move the hairs in your ears stimulating the nerves in your ears to send electrical impulses to your brain.
4. ATP is cleaved to ADP allowing ions to be transported across a membrane.
http://en.wikipedia.org/wiki/Activation_energy
If you read the site at the above link, you will see that it is purely energy required to make a reaction occur. As such, 1-4 above don't qualify do they?
Well my choices are either all of them or one of them. ithink I'm even more confused now.