Analogies in Science

Science: KS3, topic 4.1.3

Analogies are used in science to help explain difficult concepts.

Analogies are a comparison of the similarities between two concepts.
In Science analogies are usually comparing something abstract and hard to imagine to something that most people are aware of.
If used well, they well help in the understanding of a concept.
They often increase the interest in a subject.

Analogies will only work if the person is aware of the thing or context that something is being compared to.
Care should be taken when using and developing analogies that no misconceptions are developed.

A common analogy is water flowing through pipes for blood flowing through vessels.
Another analogy is comparing the immune system to police catching criminals.
The immune system protects us against viruses and bacteria.
Comparing the human eye to a camera is also a common analogy.
Both have lenses to focus the light.
The Iris controls how much light enters the eye through the

Flowing water is also used as a model for electricity.
With the pipes for wires.
A pump for the battery.
Different sizes pipes link to the resistance of the circuit.
The Earth is often compared to the layers of a peach.
There is a hard core (stone), soft mantle (flesh), and the crust (skin).
However there are problems with this analogy for instance the mantle of the Earth moves by convection currents and the skin is one not broken up into pieces or continents.

Test yourself on Analogies in Science

Which comparison is not an analogy used in science?
The immune system protects the body against viruses and bacteria, like police who catch criminals. Why does this comparison work well?
The electricity analogy compares pipes to wires, a pump to a battery, and pipe size to resistance. The blood-flow analogy only compares pipes to blood vessels and water to blood. Why does the electricity analogy explain more about circuits than the blood-flow analogy explains about blood vessels?