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la Assume the roller coaster experiences no friction. What would be the speed of the rollercoaster at point F? Defend your answer in 1-2 sentences. (2 points)Speed at Point Fin mis:The reason is:

la Assume the roller coaster experiences no friction. What would be the speed of the-example-1
User AXM
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1 Answer

21 votes
21 votes

The conservation of mechanical energy states that:


K_i+U_i=K_f+U_f

Where K is the kinetic energy and U is the potential energy. We know that the potential energy is given as:


K=(1)/(2)mv^2

and the potential energy is given as:


U=mgh

We know that in point A the velocity is zero, then the kinetic energy in that point is zero. We also know the heights in point A and F then we can plug the vaus we know in the conservation of energy and solve for the velocity in point F:


\begin{gathered} mgh_A=(1)/(2)mv^2+mgh_F \\ gh_A=(1)/(2)v^2+gh_F \\ gh_A-gh_F=(1)/(2)v^2 \\ v^2=2(gh_A-gh_F) \\ v=\sqrt[]{2g(h_A-h_F)} \\ v=\sqrt[]{2(9.8)(30-15)} \\ v=\sqrt[]{294} \\ v=17.15 \end{gathered}

Therefore the velocity in point F is 17.15 m/s

User Pregmatch
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