O Level Science Notes Archives - Page 10 of 33 - Free ZIMSEC & Cambridge Revision Notes

Galvinasing iron

By garikaib|2025-02-12T09:31:31+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Corrugated iron sheets are galvanised. Image credit alibaba.com ZIMSEC O Level Combined Science Notes: Galvinasing iron

Galvanising is one of the methods used to prevent iron from rusting
Iron and steel can be coated with zinc
Zinc is a fairly more reactive metal

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The production of Nitric acid
Gallery
The production of Nitric acid

Notes, O Level Science Notes, Ordinary Level Notes

The production of Nitric acid

By garikaib|2025-02-12T08:58:32+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

ZIMSEC O Level Combined Science Notes: The production of Nitric acid

Some of the ammonia produced using the Haber process is used in the production of nitric acid
The first stage in the process of making nitric acid is the oxidation of ammonia
To form nitric acid
\text{ammonia + oxygen} \rightarrow\text{nitric oxide+ water+heat}
This an exothermic reaction

[…]

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The Petrol engine

By garikaib|2025-02-12T09:13:38+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Four Stroke Petrol Engine. Image credit petrolheadkenya.com ZIMSEC O Level Combined Science Notes: The Petrol engine

Four strokes are involved in the operation of most petrol engines
They are thus known as four-stroke engines
The first stroke is known as the inlet stroke
During the […]

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Experiment: Determining the resistance of resistors in parallel and in series

By garikaib|2025-02-12T09:29:49+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Resistors in series ZIMSEC O Level Combined Science Notes: Experiment: Determining the resistance of resistors in parallel and in series

Aim: To determine the combined resistance of resistors in series and in parallel

Materials: 4 cells, 2 bulbs/2 resistors, switch, ammeter, voltmeter, leads with crocodile clips

Method Resistors in [...]
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Experiment: Generating electricity

By garikaib|2025-02-12T09:44:30+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

A dynamo. Image credit wikihow.com ZIMSEC O Level Combined Science Notes: Experiment: Generating electricity

Aim: To generate electric current

Materials: dynamo, lamp bulb, copper wires, crank or a set of pulleys and weights to turn dynamo, rubber band

Method

Set up the apparatus with the dynamo on a table, the rubber […]

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Testing the strength of various beams

By garikaib|2025-02-12T09:09:02+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Testing the strength of beams ZIMSEC O Level Combined Science Notes: Experiment: Testing the strength of various beams

Aim: To make different shaped beams and test their strength

Materials: thin pieces of poplar wood, sharp knife, weights, 2 clamps, 2 bricks

Cut beams about 20cm long with different cross-sectional […]

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Experiment: Comparing the strength of natural timber and other construction materials

By garikaib|2025-02-12T09:25:11+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Comparing the strength of various materials ZIMSEC O Level Combined Science Notes: Experiment: Comparing the strength of natural timber and other construction materials

Aim: To compare the strength of some natural timbers and other materials

Materials: Plywood, hard wood cut across the grain, soft wood cut along the grain, […]

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Experiment:Lifting weights using pulleys

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

Testing pulleys using a test meter ZIMSEC O Level Combined Science Notes: Experiment:Lifting weights using pulleys

Aim: To use pulleys to lift loads

Materials: 4 single pulleys, string, 1kg mass/a tin filled with sand, spring balance, clamp stand, meter rule

Method

Set up a fixed pulley as shown above

[…]

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People and Energy

By garikaib|2025-02-12T09:15:19+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Construction workers require a lot of energy. Image credit nehandaradio.com ZIMSEC O Level Combined Science Notes: Experiment: People and Energy

While it is true that everyone needs energy for metabolism and daily activities
Different people have different food needs
Food requirements can […]

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Male Reproductive system

By garikaib|2025-02-12T09:32:17+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Image credit raanetwork.org ZIMSEC O Level Combined Science Notes: Male Reproductive system

February 2025