00:01
Hi, here three different questions.
00:04
There are three different questions in this given problem.
00:07
First of all, in question number five, mass of the object, this is given as 20 kilogram.
00:24
Coefficient of friction here, this is 0 .4.
00:28
In the first part of this problem, question number five, force of gravity fg, that is the weight of this object and that is 20 into 9 .8 which comes out to be equal to 196 newton answer for the first part of this problem then in the second part of the problem normal reaction considering the surface to be horizontal normal reaction fn that will be equal to force of gravity because they cancels out they cancel out each other means this is also equal to 196 newton then in the third part of the problem force of friction small f this will be equal to mu times the normal reaction in this is 0 .4 into 196 newton means it comes out to be equal to 78 .4 newton.
01:55
Now in another question question number 6 coefficient of kinetic friction here that is given as 0 .1, 67.
02:06
Coefficient of static friction this is 0 .42.
02:12
Normal reaction this is given as 200 newton and as object is moving.
02:21
So here kinetic friction will be there.
02:47
There should be kinetic friction.
02:51
So this friction fk will be given by mu k times the normal reaction.
03:01
So this is 0 .167 multiplied by 200 newton.
03:06
Or it comes out to be equal to 33 .4 newton answer for this question number 6 here.
03:20
Then in the last question question number 7 there is some problem.
03:28
It looks to be some error here.
03:32
Mass of the object is given as 80 kilogram...