00:01
In this question we are given that we have a globe of mass 14 .2 kilogram that is resting on this horizontal layer.
00:13
A force f is acting at an angle of theta is given to us as 20 .8 degrees.
00:23
So we need to calculate the minimum value of f so that block starts moving.
00:28
Look, what is the frictional force acting on any object? fricksonal force is it is equal to destabilizing force.
00:47
Up to what point of time until unless it is destabilizing force is more than or equal to the mu static into n.
00:59
This is what f max, maximum frictional force available.
01:06
Once it is closed then what is the frictional force acting? it is mu kinetic into n.
01:13
Because before moving, the object will experiencing static friction.
01:19
So to move any object, we must apply a force at least equal to new static into n.
01:27
Over here, if you try to do the free -body diagram, the onward would be 142.
01:32
Upward would be this normal.
01:35
And if you break this f into two components, f -force 20 .8 and f -sign 20 .8.
01:44
This is the frictional force that is new static into n.
01:48
So in case of limiting conditions this normal would be equal to 1 142 minus f sign 20 .8 and new is what new static is 0 .55 0 .5 5 5 and 2 normal is 142 minus f sign 20 .8 that must be equal to f course 20 .8 right this comes from what sigma f vertical has to be 0.
02:26
This comes from sigma f horizontal has to be zero in the limiting condition.
02:32
All right.
02:34
This f is now required...