Engineering Statics

William Haynes commented on 16. Equivalent Systems, Resultants 2 years, 9 months ago

Added question: equivalent force couple system on bracket

William Haynes on Equivalent Force-couple system: Bracket 2 years, 9 months ago

Gave some feedback: Ready to use

William Haynes on Equilibrium of a rigid body: beam and pulley 2 years, 10 months ago

Saved a checkpoint:

Properly italicized variables, reformatted advise.

William Haynes on Equilibrium of a rigid body: Truss 2 years, 10 months ago

Saved a checkpoint:

When b=2.8, h=4, B=2, C=5, F=4, E=3, then Ay = 0, but  Numbas calculates it as Ay = -1.7763568394002505*10^(-15) and marks 0 wrong, because it calculates percent error to be 100 %

abs(0 - 0.00000000000002)/(0.00000000000002) = 1.

Added precround(Ay,6) in Marking settings to avoid this.  I don't know how to fix the root cause.

William Haynes on 13. Equilibrium of Rigid Bodies 2 years, 10 months ago

Saved a checkpoint:

Student reports that when A_y = 0, answer is not marked correct.

William Haynes on Equilibrium of a particle: four forces 2 years, 10 months ago

Gave some feedback: Has some problems

William Haynes on Equilibrium of a particle: four forces 2 years, 11 months ago

Saved a checkpoint:

Problem is throwing "undefined is not an object (evaluating 'original_result.states.mark')" when answer is submitted.  Resubmitting it works.  

William Haynes on Equilibrium of a particle: four forces 2 years, 11 months ago

Saved a checkpoint:

No bug, student misinterpreted the question leading to his problem

William Haynes on Equilibrium of a particle: four forces 2 years, 11 months ago

Saved a checkpoint:

Bug in marking algorithm reported

William Haynes on Friction: Range of values 2 2 years, 11 months ago

Gave some feedback: Ready to use

William Haynes on Friction: Range of values 1 2 years, 11 months ago

Gave some feedback: Ready to use

William Haynes on Friction: Determine direction of $F_f$ 2 years, 11 months ago

Gave some feedback: Ready to use

William Haynes on Friction: block on block 2 2 years, 11 months ago

Gave some feedback: Ready to use

William Haynes on Friction: block on block 1 2 years, 11 months ago

Gave some feedback: Ready to use