## Saturday, June 23, 2012

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### Ratio defination and formula

Mechanical Advantage of a machine is defined as a ratio of a load overcome by the machine to the effort applied in the machine.
Mathematically,
effort
i.e            MA=    L
E

It has no unit as it is the ratio of  two force.

What is meant by a simple machine having MA3?
It meant that we can overcome the load of 3 Newton (N)  by applying the effort of 1N using simple machine.

Velocity Ratio (VR)
Velocity Ratio is defined as a  ratio of effort distance to load distance.

Mathematically,
VR=    effort distance
i.e             VR   ED
LD

Efficiency
It is the ratio of work output to work input per 100%.

Mathematically,
Efficiency=    Work output
Work Input
=Í LD
E Í ED

=  L  Í  LD
E       ED
=   L    ÷ ED
E       LD
=  MA ÷ VR
=   MA
VR
i.e   Efficiency=   MA
VR