1.It is the upward force exerted by the ground that pushes you up, but this force can never exceed your weight.
2) You are able to spring up because the earth exerts a force upward on you that is stronger than the downward force you exert on the earth.
3) When you push down on the earth with a force greater than your weight, the earth will push back with the same magnitude force and thus propel you into the air.
4) When you jump up the earth exerts a force F1 on you and you exert a force F2 on the earth. You go up because F1 > F2.
<span>5) Since the ground is stationary, it cannot exert the upward force necessary to propel you into the air. Instead, it is the internal forces of your muscles acting on your body itself that propels the body into the air.</span>
There is a probability that heat will flow from warmer to cooler substances,
and a probability that heat will flow from cooler to warmer substances.
The probability that heat will flow from a cooler to a warmer substance is
so small that it is ignored. It's accepted as a 'law' of thermodynamics that
heat always flows from higher temperature to lower temperature.
An ocean is an example of a wave form
Particles in the solar nebula were more spread out at greater distances, so that accretion took longer and there was less time to pull in gas before the solar wind cleared the nebula.
