If the coefficient of kinetic friction between a 22- kg crate and the floor is 0.30, what horizontal force is required to mive the crate at a steady soeed across the floor? what horizontal force is required if it is zero?

Horizontal force to move the crate at a steady speed across the floor is 64.746 N

There is no horizontal force when coefficient of friction is zero.

Given :

Mass = 22 kg

Coefficient of friction = 0.30

a = 0, because crate moving at a steady speed.

Solution :

Horizontal force to move the crate at a steady speed across the floor is,

F = ma                   (According to Newton's second law)

         (since acceleration is zero)

Now, when coefficient of friction is zero than friction force is also zero. Therefore horizontal force is,

F = 0

So, there is no horizontal force when coefficient of friction is zero.

For more information refer the link given below

link

d

explanation:

v=uf/(u-f)

= 5.10/(5-10) convex lens has positive focal length

=50/-5

=-10 cm (formed at other side)

i am pretty sure it is c because when people are closer together, they cannot move as freely. picture being in a mostly full elevator, for instance. the people are right next to you, and you can barely move.