Answer:
The skater has mechanical/gravitational potential energy at the two meter mark. The skater gets to two meters high on the other end of the ramp. In terms of the conservation of energy, the skater will never go higher than two meter on the other end of the the ramp because energy can be neither created nor destroyed.
Explanation:
I hoping it is right!!!∪∧∪ ∪ω∪
Answer:
Yes, it would make it back up.
Explanation:
If it has 100,000 Joules of gravitational potential energy at the top of the hill, by the time the cart gets to the bottom, it will become PE = 0, KE = 90,000 since 10% of 100,000 is 10,000. The cart only requires 80,000J to climb back up so it should easily do so.
I didn't quite understand if the 10% energy loss is total, or every time it goes up or down, but it isn't a problem because 10% of 90,000 is 9,000, which means it would have 81,000J of energy on the way back up IF it loses energy due to friction on the way back up also.
The only physical law you need to prove this is the Law of Conservation of Energy: no energy is lost, only transformed; 10% of the energy becomes heat, the rest remains mechanical energy, which is the reason why the reasoning above works.
Yes. While we're using the natural gas that was created by the decomposition
of dead dinosaurs, we're also manufacturing more of it, by the decomposition
of potato peels and dirty diapers in land fills, and of leaves, trees, and dead
wildlife everywhere on Earth.
The new stuff will be ready to extract and use in a million years or so.
That's the problem ... not that natural gas is exhaustible, but that we're using it
much much faster than it can be regenerated. So on the time-scale of our
requirements, it's a limited resource, and it's very possible to run out of it.
It's exactly the same as spending money faster than you earn it.
And so is oil.