can some one help me set up an equation for potential and kenetic energy

Question

anonymous · Answer

@zepdrix

anonymous · Answer

@jigglypuff314

ddcamp · Answer

Yeah, I can help.

anonymous · Answer

yay 
ok so first how do i find the pe

ddcamp · Answer

What's the scenario?

anonymous · Answer

ok so i made a roller coaster and i have to find... http://classjump.com/c/cojophysics/documents/Roller_Coaster_Project.doc

ddcamp · Answer

OK, on a roller coaster the potential energy all comes from gravity:
$$U = mgh$$

anonymous · Answer

is that mass x gravity x height?

ddcamp · Answer

Yes

ddcamp · Answer

And kinetic energy is always the same:
$$K = \frac{ 1 }{ 2 } mv^2$$

anonymous · Answer

how do i find the mass? 
1cm=7 m my height is 32cm

ddcamp · Answer

One of the cool things with conservation of energy is that mass cancels out:
$$\Delta U = \Delta K \ mg \Delta h = \frac{ 1 }{ 2 } m \Delta v^2 \ g \Delta h = \frac{ 1 }{ 2 } \Delta v^2$$

anonymous · Answer

even for potential?

ddcamp · Answer

Yup.
The velocity at any height can be found by solving the conservation equation for v:
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