00:01
Let's talk about this question.
00:04
We are given that if the coefficient of the kinetic friction, the kinetic friction between a 22 kilogram kilogram crate and the floor is 0 .3, then what horizontal force is required to move the crate at a constant speed across the floor? so the word constant speed is really, steady speed is really important because steady speed means that the acceleration is zero because the speed is not changing.
00:34
And if the acceleration is zero, it means that the net force acting on the crate must be zero.
00:40
So if you are going to draw a simple figure, let's say this is the crate and this is how we are pushing it from this force if.
00:49
So the friction is going to be over here and this is the reaction force and this is the weight.
00:57
If the net force is zero, it means that the friction force is definitely equal to the force which we are applying.
01:04
So, and friction forces, mu k times the reaction force, and the reaction force is nothing but equal to weight.
01:11
Now, value of mu is given as 0 .3 weight is mass times acceleration due to gravity, which is 9 .8...