Asked by James
A 16-kg child sits on a 5-kg sled and slides down a 143-meter, 30-degree slope, to the nearest m/s what is his or her speed at the bottom?
Answers
Answered by
drwls
They want you to neglect friction and use conservation of energy. The masses will not affect the result.
g*L*sin30 = V^2/2
L = 143 m
g = 9.81 m/s^2
Solve for V, and round to nearest m/s
The m/s number that you get will correspond to well over 100 miles per hour - a very unsafe value.
There will actually be appreciable friction unless they are on an ice-covered luge run, and using no brakes or foot dragging.
This is a rather unrealistic problem.
g*L*sin30 = V^2/2
L = 143 m
g = 9.81 m/s^2
Solve for V, and round to nearest m/s
The m/s number that you get will correspond to well over 100 miles per hour - a very unsafe value.
There will actually be appreciable friction unless they are on an ice-covered luge run, and using no brakes or foot dragging.
This is a rather unrealistic problem.
Answered by
James
THANKYOU
Answered by
James
Thank you drwls, there is another question that I am not getting really well right now. It is this: Two skaters are in the exact center of a circular frozen pond. Skater 1 pushes skater 2 off with a force of 100 N for 1.4 seconds. If skater 1 has a mass of 30 kg and skater 2 has a mass of 74 kg, what is the relative velocity (v1 - v2) after the push to the nearest hundredth of a m/s? After reaching the other shore, how fast, to the nearest tenth of a m/s, must skater 1 run around the lake to meet skater 2 at the opposite shore?
Thanks
Thanks