00:01
Hello, here we have the following problem.
00:02
Let's suppose a skip patch lowers rescue sled and victim, and the total mass is 80 kilograms.
00:12
They are lowered down a 66 degree slope, and the coefficient of kinetic friction is 0 .00.
00:22
And the speed is constant.
00:26
First, in question a, we have to calculate the work done by friction as the sled moves 30 meters along the hill.
00:39
Let's sketch the forces acting in here.
00:59
So, and first of all, we have to determine where, yeah, we have to determine work done by the friction force.
01:09
So this work is negative because the displacement is downwards.
01:21
And therefore, this work is negative.
01:26
M g cosine teta times d or times l to be precise that's negative 900 and 57 joules now let's move on to the next question question b we have to calculate the work done by the rope so it means that we have to calculate there we have to determine whether the extension is directed and to determine the direction of t, we have to calculate the difference between g, between sine teta and m.
02:44
K...