Pulley-system virtual work

Apply constraint-compatible virtual displacements to levers, pulleys, mechanisms, and force-direction optimization.

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Advanced engineering statics simulation

Virtual Work Equilibrium Suite

Five distinct, constraint-compatible virtual-work models; efficiency is separated from geometry.

Simulation

Use the rope-length constraint δsin=nδy; efficiency changes required force, not the kinematic displacement ratio.

Applied load120 N

20–400

Drag for exploration or enter an exact value. Press Enter to apply and Escape to restore.

Supporting rope segments4

1–10

Drag for exploration or enter an exact value. Press Enter to apply and Escape to restore.

Mechanical efficiency0.90

0.50–1.00

Drag for exploration or enter an exact value. Press Enter to apply and Escape to restore.

compatible virtual motion

Required input

33.333 N

Virtual-work residual

1.42e-14 N

Should be near zero

Rope displacement ratio

4:1

Geometry only

Efficiency

90.0%

Changes force, not rope constraint

\delta s_{in}=n\,\delta y,\qquad \eta P\delta s_{in}-W\delta y=0

The number of supporting segments fixes displacement compatibility. Efficiency accounts for loss in the work balance.

Model scope and verification

Scope: Educational rigid-body statics model using the selected geometry, stated idealizations, and displayed SI units.

Acceptance check: Check the governing equilibrium, compatibility, geometry, or limiting-condition statement before accepting the numerical result.

Lever equilibrium Scissor mechanism Small-displacement compatibility Minimum-input-force direction

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