Free WACE Physics Flashcard Review

It states exactly how a quantity is changed or measured, including instrument, method and units, so another investigator can repeat the procedure.

Averaging can reduce the influence of independent random scatter. A shared zero offset remains systematic and requires calibration or correction.

A best-fit line estimates the overall relationship while allowing measurement scatter. Joining points treats each fluctuation as physical structure without evidence.

A clearly named physical quantity and its unit. Use a scale that displays the data adequately; an axis need not begin at zero unless the interpretation requires it.

Plot measured minus predicted values. Random scatter about zero supports the fit; systematic curvature or a trend suggests an omitted effect or an unsuitable relationship.

Precision concerns agreement among repeated measurements. Accuracy concerns closeness to an accepted value. Readings may cluster tightly around a biased value.

Use 100Δx/|x|. This compares the absolute uncertainty with the magnitude of the measured value; both must use compatible units.

Add fractional uncertainty bounds: Δ(xy)/|xy|≈Δx/|x|+Δy/|y|. State the adopted method; statistical independent standard uncertainties may instead combine in quadrature.

It establishes an offset in the fitted relationship within uncertainty. It may represent a real physical quantity or calibration bias; the graph alone does not decide which.

Raw observations preserve scatter, outliers and the calculation trail. They allow uncertainty and averaging choices to be checked without inventing lost precision.

The vector sum of forces is zero and the total torque about any chosen pivot is zero. Zero resultant force alone still permits angular acceleration.

Torque magnitude is force multiplied by perpendicular distance from pivot to the force’s line of action: τ=Fd⊥. Equivalently τ=rF sinθ.

Its line of action passes through that pivot, so its moment there is zero. This can remove that unknown from the torque equation without claiming the force is absent.

At its centre of mass, halfway along its length. Include this weight separately from any supported loads.

Its moment magnitude is 40×0.300=12.0 N m. Clockwise or anticlockwise depends on force direction and which side of the pivot it acts.

Yes. Their vector sum and combined torque can both be zero. Equilibrium does not mean absence of forces.

The contact reaction at one edge falls to zero and the body is about to rotate about the remaining support edge. Compare moments about that edge.

Only its vertical component contributes to vertical force balance. For angle θ above horizontal this component is T sinθ; the horizontal component must also be balanced.

Two equal, opposite, parallel forces separated by a perpendicular distance. Their resultant force is zero but they produce a nonzero torque independent of pivot choice.

Although the dimensions match energy, torque describes rotational effect and has direction. Writing N m preserves the distinction from scalar work or energy.