A small block of mass m = 3.0 kg begins at height h = 18 m above the ground. It
ID: 2297062 • Letter: A
Question
A small block of mass m = 3.0 kg begins at height h = 18 m above the ground. It slides down a frictionless surface and encounters a loop of radius R = 6 m, as shown in the figure.
What is the speed of the block at the bottom of the loop?
What is the speed of the block at the top of the loop?
How much work does gravity do as the block moves from its highest to its
lowest point?
How far will the block travel before stopping if a coefficient of kinetic
friction ?k ? 0.25 exists between the block and the part of the track after
the loop?
What is the work done by friction in this case?
Explanation / Answer
1)m*g*h=0.5*m*v^2
v=18.7829 m/s
2)h=12 m now same fromula above
v=15.336 m/s
3)*m*g*h=529.2 j
4)after loop energy is still 529.2 j
529.2 j= (0.25*3*9.8)*d
d=72 m
6)529.2 j