Lesson Notes By Weeks and Term - Junior Secondary School 3

SUBJECT:�BASIC SCIENCE���

CLASS:� JSS3

DATE:

TERM: 3RD TERM

WEEK 4

TOPIC: CONTROLLING THE WEATHER

Weather is the state of condition of the atmosphere at a given time. It is a state of the atmosphere with regards to temperature, wind, precipitation, air pressure and other factors.

Meteorology is the scientific study of the atmosphere and the changes that take place in weather. Meteorologist forecast the future condition of weather by studying, observing, recording and analyzing the condition of the atmosphere.

EVALUATION

1. What is meteorology?
2. Define weather.

SUBTOPIC: SIMPLE WEATHER CONDITION

1. Temperature: is the degree of hotness or coldness of a body. In weather observation, temperature is measured by an instrument called the maximum and minimum thermometer.
2. Rainfall: The amount of rainfall is measured by an instrument called the rain-gauge. After rainfall, the volume of water collected is measured using graduated cylinder.
3. Atmospheric Pressure: Pressure is defined as force per unit area. The bombardment of a surface by particles gives rise to pressure.

��� The instrument used for measuring pressure is called the barometer.

4. Relative humidity: is the ratio of the amount of moisture in the air that could hold temperature if it were completely saturated.

��� When air is saturated, relative humidity is high; rainfall is quite likely and vice versa. The instrument normally used to measure the amount of water vapour in the air is wet-and-dry bulb thermometer known as hygrometer.

5. Wind direction is measured by using wind vane.
6. Wind speed is measured by using anemometer.

EVALUATION

1. What is relative humidity?
2. Name six important instruments for measuring weather

SUBTOPIC:� EFFECT OF WEATHER ON HUMAN ACTIVITIES

Weather plays an important part in human activities. Weather changes constantly. One day it is dry and sunny, the next day cloudy and rainy. Farmers need good weather so that crops can grow and ripe.

Rainfall could have prevented you from coming to school or disturbed parts of your programme.

Weather sometimes affects sales in market places. Transportation and communication also suffer in bad weather.

Note:

1. The line on a chart joining all places having the same amount of rainfall is called isohyets
2. The line on a chart which joins all places having the same barometric pressure is called isobar
3. The line on a chart which joins all places having the same temperature is called isotherm.

WEEKEND ASSIGNMENT

1. The instrument used in measuring air pressure is ______

��� (a) Anemometer (b) hygrometer (c) barometer (d) thermometer

2. The degree of distance to which things can be seen under certain weather conditions is called _____ (a) wind vane (b) visibility (c) feasibility (d) clouds
3. All the following affect the weather of a place except_____

��� (a) Wind (b) humidity (c) gravity (d) rainfall

4. The speed of the wind can be determined, using an instrument called ____ (a) wind vane (b) anemometer (c) barometer (d) rain gauge

THEORY

1. What is weather?
2. Mention six factors that can affect weather.

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