science notes Archives - Page 25 of 32 - Free ZIMSEC & Cambridge Revision Notes

Copper and its alloys

By garikaib|2025-02-12T09:24:43+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Copper and its alloys. Image credit zzhi.com ZIMSEC O Level Combined Science Notes:Copper and its alloys

Copper is a common element found in the earth’s crust
It can occur as an element, as copper oxide or as sulphide ore
In Zimbabwe:
Sulphide copper deposits […]

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Rusting and Painting
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Rusting and Painting

Notes, O Level Science Notes, Ordinary Level Notes

Rusting and Painting

By garikaib|2025-02-12T09:39:40+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

ZIMSEC O Level Combined Science Notes: Rusting and Painting

Painting is a popular method used to prevent rusting
The structure to be painted is cleaned using an acidic solution
This removes existing rust and dirt
Sand paper/scrubbing material is also used to clean the surface to be painted
The surface is then left to dry
Once it is dry […]

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Biogas as a source of energy
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Biogas as a source of energy

Notes, O Level Science Notes, Ordinary Level Notes

Biogas as a source of energy

By garikaib|2025-02-12T09:06:04+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

ZIMSEC O Level Combined Science Notes: Biogas as a source of energy

Biogas is the gas that is obtained from fermenting manure and other organic waste
It is a mixture of methane, carbon dioxide and hydrogen sulphide
Cattle manure is commonly used as a waste to feed biogas plants
Small plants have been built in some parts of Zimbabwe

[…]

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Conductors and insulators

By garikaib|2025-02-12T09:18:48+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Conductors and Insulators. Image credit sci-toys.com ZIMSEC O Level Combined Science Notes: Conductors and insulators

A conductor is a material that allows electrons to move from one atom to another
Conductors/Conducting materials cannot be charged unless they are held using an insulating material to prevent […]

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The dry electric cell

By garikaib|2025-02-12T09:37:08+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

The components of a dry cell ZIMSEC O Level Combined Science Notes: The dry electric cell

About 1.5 V is produced in a dry cell
This voltage falls as the voltage falls as the cell goes “flat” as the chemicals are used up
A dry […]

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A simple D.C motor

By garikaib|2025-02-12T09:02:26+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

dc_motor-min DC motor. Image credit kostov-motors.com ZIMSEC O Level Combined Science Notes: Experiment: Demonstrating that an electric wire moves in a magnetic field

A DC motor converts direct electric current into kinetic energy
It has a stator
Stator-a stationary magnet found within a DC motor
It also has a many coils […]

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Experiment: Testing the strength of various joints

By garikaib|2025-02-12T09:18:29+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Welding joints. Image credit youtube.com ZIMSEC O Level Combined Science Notes:Experiment: Testing the strength of various joints

Aim: To test the strength of various joints in beams

Materials: pieces of metal,poplar wood, glue, drawing pins/nails, bolts and nuts, old plastic rulers, burner, bricks/clamp, welding equipment/burner

Method Testing [...]
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