Get premium membership and access questions with answers, video lessons as well as revision papers.
Effects of anomalous expansion of water
a. Biological importance
During cold weather, the temperature of lakes and ponds drops and water contracts, becomes denser and sinks.
A circulation of water is thus set up until all the water attain maximum density i.e. at 4oC. If further cooling occurs (below 4oC), then any water below 4oC will stay at the top due to its lower density. At 0oC, ice forms on top and this acts as an insulator to the layers below. Hence the warmth underneath can sustain aquatic life and thus the aquatic animals and plants can survive there.
b. Icebergs
Ice has a slightly lower density, about 0.92 g/cm3, than that of water and hence it floats with a small portion above the water surface. The rest and a bigger portion of the ice rests under water. This is called an iceberg.
Icebergs pose a great danger to ships as the submerged parts cannot be seen easily by navigators.
c. Weathering of rocks
Water sometimes finds its way into cracks within the rocks. When such water freezes during cold weather, it expands forcing the rock to break into smaller pieces. This is very important for agriculture as soil is formed.
d. Bursting of water pipes
At times the water flowing through a pipe may freeze when it passes through a cold region. The water thus contracts, expanding and this may lead to pipe bursts if expansion allowances were not catered for.
chrispohmomanyi answered the question on October 4, 2017 at 06:18
- Give three ways in which the power of an electric motor can be increased.(Solved)
Give three ways in which the power of an electric motor can be increased.
Date posted: October 4, 2017. Answers (1)
- State the effect of adding sodium chloride to ice at 0 degrees.(Solved)
State the effect of adding sodium chloride to ice at 0 degrees.
Date posted: October 4, 2017. Answers (1)
- Explain the function of the small hole at the side of the cover of a ball point pen. (Solved)
Explain the function of the small hole at the side of the cover of a ball point pen.
Date posted: October 4, 2017. Answers (1)
- Why is the inner part of a pinhole camera painted black?(Solved)
Why is the inner part of a pinhole camera painted black?
Date posted: October 4, 2017. Answers (1)
- How does a syringe draw water from a beaker.(Solved)
How does a syringe draw water from a beaker.
Date posted: October 4, 2017. Answers (1)
- Explain why a concave meniscus is formed on the surface of water while convex meniscus on mercury liquid.(Solved)
Explain why a concave meniscus is formed on the surface of water while convex meniscus on mercury liquid.
Date posted: October 4, 2017. Answers (1)
- State the purpose of carbon powder in a dry cell.(Solved)
State the purpose of carbon powder in a dry cell.
Date posted: October 4, 2017. Answers (1)
- State two ways of increasing the mechanical advantage of a hydraulic machine.(Solved)
State two ways of increasing the mechanical advantage of a hydraulic machine.
Date posted: October 4, 2017. Answers (1)
- State and explain how stability of the candle changes as it continues to burn.(Solved)
State and explain how stability of the candle changes as it continues to burn.
Date posted: October 4, 2017. Answers (1)
- An FM radio station aired its transmission at the frequency of 100 Mega Hertz. Calculate its wavelength given that the velocity of the wave is...(Solved)
An FM radio station aired its transmission at the frequency of 100 Mega Hertz. Calculate its wavelength given that the velocity of the wave is 3.0 x 10^8 m/s
Date posted: October 2, 2017. Answers (1)
- The strength of an electromagnet can be increase by certain modifications. State the two likely ways
one...(Solved)
The strength of an electromagnet can be increase by certain modifications. State the two likely ways
one can do this.
Date posted: October 2, 2017. Answers (1)
- When girl was carrying a bucket full of water she leaned away from it. State the reason.(Solved)
When girl was carrying a bucket full of water she leaned away from it. State the reason.
Date posted: October 2, 2017. Answers (1)
- Oil was accidentally spilled over a large surface area of the ocean. State two environmental hazards
that...(Solved)
Oil was accidentally spilled over a large surface area of the ocean. State two environmental hazards
that the oil may cause.
Date posted: October 2, 2017. Answers (1)
- Iron fillings were found to cling in large quantities at the ends of a bar magnet.
Explain this...(Solved)
Iron fillings were found to cling in large quantities at the ends of a bar magnet.
Explain this observation.
Date posted: October 2, 2017. Answers (1)
- A student took an accumulator to be charged. He was advice to leave the caps of the cell open. Give the
...(Solved)
A student took an accumulator to be charged. He was advice to leave the caps of the cell open. Give the
reason for doing this.
Date posted: October 2, 2017. Answers (1)
- A lady wearing sharp pointed heeled shoes walked through a banking hall lined with wooden tiles. State
...(Solved)
A lady wearing sharp pointed heeled shoes walked through a banking hall lined with wooden tiles. State
what is likely to happen.
Date posted: October 2, 2017. Answers (1)
- Wide tyres are fitted on a vehicle to reduce pressure exert on the road. Explain.(Solved)
Wide tyres are fitted on a vehicle to reduce pressure exert on the road. Explain.
Date posted: October 2, 2017. Answers (1)
- From the expression P = pgh. State the factors that affect pressure of a fluid.(Solved)
From the expression P = pgh. State the factors that affect pressure of a fluid.
Date posted: October 2, 2017. Answers (1)
- Give one function of the cylindrical anodes in the CRO. tube.(Solved)
Give one function of the cylindrical anodes in the CRO. tube.
Date posted: October 2, 2017. Answers (1)
- Atmospheric pressure decreases with increase in height. Explain(Solved)
Atmospheric pressure decreases with increase in height. Explain
Date posted: October 2, 2017. Answers (1)