Turning Effect 1

The diagram shows an object of weight \(W\) and an object of weight \(Z\) balanced on a uniform metre rule.

                                   
Which equation relating to \(W, Z\), \(a\) and \(b\) is correct?

Five identical bags of rice are balanced on a uniform beam by an object of mass \(10 \mathrm{~kg}\).

                             
Two more identical bags of rice are added to the other five. The average position of the bags on the beam does not change.
What mass now balances the bags?

The diagram shows an unbalanced rod. Two loads \(\mathrm{X}\) and \(\mathrm{Y}\) can be moved along the rod.

                     
The rod turns in a clockwise direction as shown.
Which action could make the rod balance?

The diagram shows a balance being used to find the weight of a baby. The weight of the basket can be ignored.
At equilibrium, the pivot is nearer to the \(40 \mathrm{~N}\) balancing weight than to the baby.

                             
What is the weight of the baby?

The diagram shows a uniform beam being used as a balance. The beam is pivoted at its centre.
A \(1.0 \mathrm{~N}\) weight is attached to one end of the beam. An empty pan weighing \(0.2 \mathrm{~N}\) is attached to the other end of the beam.

                                     
How many \(0.1 \mathrm{~N}\) weights must be placed on the pan in order to balance the beam?

A heavy beam rests on two supports. The diagram shows the only three forces \(F_1, F_2\) and \(F_3\) acting on the beam.

                                     
The beam is in equilibrium.
Which statement is correct?

A uniform rod rests on a pivot at its centre. The rod is not attached to the pivot. Forces are then applied to the rod in four different ways, as shown. The weight of the rod can be ignored.
Which diagram shows the rod in equilibrium?

A wooden bar is pivoted at its centre so that it can rotate freely. Two equal forces \(F\) are applied to the bar.
In which diagram is the turning effect greatest?

The weight of an object is found using the balance shown in the diagram. The object is put in the left-hand pan and various weights are put in the right-hand pan.

                                   
These are the results.
\[
\begin{array}{|c|c|}
\hline \text { weights in the right-hand pan } & \text { effect } \\
\hline 0.1 \mathrm{~N}, 0.1 \mathrm{~N}, 0.05 \mathrm{~N}, 0.02 \mathrm{~N} & \text { balance tips down slightly on the left-hand side } \\
\hline 0.2 \mathrm{~N}, 0.1 \mathrm{~N}, 0.01 \mathrm{~N} & \text { balance tips down slightly on the right-hand side } \\
\hline
\end{array}
\]
What is the best estimate of the weight of the object?

The diagram shows a force being applied to a lever to lift a heavy weight.

Which change would enable the heavy weight to be lifted with a smaller force?

The diagrams show three uniform beams \(P, Q\) and \(R\), each pivoted at its centre.
The two forces acting on each beam are also shown.

                     
Which beams rotate clockwise?