Ten questions. The result tells you which lessons you may skip.
A force of \(20\,\text{N}\) acts at right angles to a door, \(0.4\,\text{m}\) from its hinge. The torque about the hinge is
A force acts on a body along a line that passes through the axis of rotation. Its torque about that axis is
A spanner is gripped \(0.3\,\text{m}\) from a nut, and a force of \(50\,\text{N}\) acts there at \(30°\) to the handle. The moment arm of the force about the nut is
A force \(\vec F = 4\hat i\,\text{N}\) acts at the point \(\vec r = 2\hat j\,\text{m}\). Its torque about the origin is
Two equal and opposite forces act on a wheel along parallel lines a distance \(d\) apart. Which statement is correct?
A \(20\,\text{kg}\) child sits \(2\,\text{m}\) from the pivot of a see-saw. For balance, a \(40\,\text{kg}\) adult on the other side must sit at
Parallel forces of \(20\,\text{N}\) and \(30\,\text{N}\) act in the same direction along lines \(1\,\text{m}\) apart. Their resultant acts at a distance from the \(20\,\text{N}\) force of
A tall box stands on a floor. It topples when
A uniform block with width \(b\) and height \(h\) such that \(b/h = 0.5\) rests on a board with \(\mu_s = 0.4\). The board is tilted slowly. The block
A uniform ladder leans at \(45°\) against a smooth wall. The least coefficient of friction at the floor that holds it is