Define moment of a force. The diagram shows a metre stick suspended from its centre of gravity. A force of 3 N acts on the stick at the 90 cm mark and a force of F N acts on the stick at the 20 cm mark. The metre stick is balanced horizontally. Calculate force F. Give an everyday example of an application of the lever, using a labelled diagram, showing the fulcrum and at least one force acting on the lever. Use the box provided for your labelled diagram.

Photo AI

Define moment of a force - Junior Cycle Science - Question c - 2007

Question c

Define moment of a force. The diagram shows a metre stick suspended from its centre of gravity. A force of 3 N acts on the stick at the 90 cm mark and a force of F ... show full transcript

Worked Solution & Example Answer:Define moment of a force - Junior Cycle Science - Question c - 2007

Step 1

Define moment of a force.

96%

114 rated

Answer

The moment of a force, also known as the turning effect or turning power, is defined as the product of the force and the distance from the fulcrum. Mathematically, it can be expressed as:

$\text{Moment} = \text{Force} \times \text{Distance from fulcrum}$

Where the units are usually in Newton-meters (Nm).

Step 2

Calculate force F.

99%

104 rated

Answer

To calculate the force F that balances the moment on the metre stick, we can use the principle of moments where the sum of moments around the fulcrum must be zero.

Applying the formula:

$30 \text{ cm} \times F = 40 \text{ cm} \times 3 \text{ N}$

Now, simplifying:

$F = \frac{40 \text{ cm} \times 3 \text{ N}}{30 \text{ cm}}$

Calculating gives:

$F = \frac{120 \text{ N cm}}{30 \text{ cm}} = 4 \text{ N}$

Thus, the force F is 4 N.

Step 3

Give an everyday example of an application of the lever.

96%

101 rated

Answer

An everyday example of an application of a lever is a spanner used to loosen or tighten a nut.

In this case, the fulcrum is located at the point where the spanner contacts the nut, while the force is applied at the end of the spanner handle to rotate the nut.

Labelled Diagram:

Fulcrum: The point of rotation (e.g., the point of contact with the nut).
Force: The downward pressure applied at the end of the handle.
Handle: The arm of the lever used to apply force.

97% of Students

Report Improved Results

98% of Students

Recommend to friends

100,000+

Students Supported

1 Million+

Questions answered

Define moment of a force - Junior Cycle Science - Question c - 2007

Worked Solution & Example Answer:Define moment of a force - Junior Cycle Science - Question c - 2007

Define moment of a force.

Calculate force F.

Give an everyday example of an application of the lever.

Join the Junior Cycle students using SimpleStudy...

Other Junior Cycle Science topics to explore