Tag: a little effort, lot of work

The mechanical advantage of a wheel and axle $= \displaystyle \frac{Radius  of  wheel}{Radius  of  the  axle} $      ..........  (1)
But $MA = \displaystyle \frac{load}{effort}$      .............    (2)
From (1) and (2)
$\displaystyle \frac{Radius  of  wheel}{Radius  of  the  axle} = \frac{load}{effort}$
$\displaystyle \frac{50  cm}{10  cm} = \frac{1000 \times  10  N}{effort}$
$Effort = \displaystyle \frac{1000  \times  10  \times 10}{50}$
$ Effort = 2000 N$

Yes it effects the effort required to lift the load as a crow bar of 7 m length provides greater effort arm than a crow bar of 5 m length. Thus crow bar of 7 m length requires lesser effort.

Centrifugation is the process of separating suspended particles from a liquid by rotating the liquid at a high speed. The mixture is taken in a closed bottle and rotated at a high speed. The heavy particles settle at the bottom while light particles remain behind. This method is used to separate cream from milk