Movement Ratio
Machines and movement ratio (velocity ratio).
A machine is a device that can change the magnitude and line of action of a force.
Examples are
 pulley systems
 gear systems
 screwjacks
A simple machine amplifies the input force (effort) to a larger output force (load).
Movement Ratio
The movement ratio (or velocity ratio) of a machine is defined as the ratio of the distance moved by the effort to the distance moved by the load. Movement ratio can be expressed as
M_{r} = s_{e} / s_{l}
= velocity ratio (1)
where
M_{r} = movement ratio
s_{e} = distance moved by the effort (m, ft)
s_{l} = distance moved by the load (m, ft)
Machine Efficiency
The efficiency of a simple machine is defined as the ratio of the force ratio to the movement ratio and can be expressed as
μ = F_{r} / M_{r} (2)
where
μ = machine efficiency
F_{r} = force ratio
Related Topics

Dynamics
Motion  velocity and acceleration, forces and torque. 
Mechanics
Forces, acceleration, displacement, vectors, motion, momentum, energy of objects and more.
Related Documents

ConnRod Mechanism
The connecting rod mechanism. 
Force Ratio
The force ratio is the load force versus the effort force. 
Motors  Speed vs. Pulley Diameter
Pulley (Sheave) selection charts for motors ranging 850  3450 rpm. 
Pulleys
Pulleys, blocks and tackles. 
Ratios and Proportions
The relative values between quantities  ratios and proportions. 
Screw Jack  Effort Force vs. Load
Screw jacks and effort forces. 
Toggle Joint
A toggle joint mechanism can be used to multiply force.