Conserv. of E and Work momentum

Thread starter saliiravezz
Start date Jul 12, 2010
Tags

Momentum Work

AI Thread Summary

The discussion revolves around a physics problem involving a roller coaster's speed at different points, considering energy conservation and work done against friction. The initial speed at point 1 is given as 1.70 m/s, and the average friction force is one-fifth of the coaster's weight. Participants are expected to apply the conservation of energy principle and work-energy equations to find the speed at point 2 after traveling 45 meters. The initial attempts indicate confusion about how to set up the energy equation correctly. The conversation highlights the importance of understanding the relationship between kinetic energy, potential energy, and work done by friction.

Jul 12, 2010

saliiravezz

Homework Statement

suppose the rlller coaster in the figure passes point 1 with a speed of 1.70m/s. If the average force of friction is equal to 1/5th of its weight, with what speed will it reach point 2? the distance traveled is 45m.

Homework Equations

conserv. of E
and Work

The Attempt at a Solution

- i don't know how to do it.

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Jul 12, 2010

bp_psy

You start by writing the energy equation.

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