SCIENCE SA 2 PREPARATION FOR PRIMARY 4

 

SCIENCE SA 2 PREPARATION FOR PRIMARY 4

1.       what are the parts of an electronic circuits? Battery, switch, wires, and bulbs.

2.       What are the function of these?

a.       Battery : the source of electricity in a circuit.

b.      Switch : controls when an electric current can flow in an electric circuit.

c.       Bulb : produces light when an electric current flows through it.

d.      Wires : connect one electrical part to another and allow electric currents to flow in a circuit.

3.       What are conductor and insulator? Give 3 examples of each conductor and insulator!

-          Electrical conductor are materials that allow an electric current to flow through them. Ex : steel, chopper, iron, aluminium

-          Electrical insulator are materials that do not allow an electri curren t to flow through them. Ex : wood, porcelain, plastic, wire, cloth

4.       What is the differences of open and closed circuits?

-          Open circuit : electric circuit through which an electric current cannot flow.

-          Closed circuit : electric circuit through which an electric current can flow.

5.       What are the activities that can make noise pollution of loud sounds?  loud music, transportation (traffic, rail, airplanes, etc.), lawn care maintenance, construction, electrical generators, explosions, and people.

6.       What is intensity?  Intensity of a sound is how loud the sound is.

7.       How to protect our ears from noise pollution of loud sounds?

-          Rest you ear in a quiet environment at night

-          Keep the volume on music player, stereos and television sets low

-          Wear protective ear plugs or earmuffs when working in places where there is constant exposure to loud sounds.

-          Avoid going to noisy places like theatres, amusement centres and games arcades for long periods of time.

8.       What are the uses of soil? Soil is used in farming, a habitat for many organism, and a raw material to make glass, cement, and pottery.

9.       Type of soil particle.

-          Sand. Sand particles are the largest size. They feel coarse, gritty, rough, and like little pieces of rocks and stones.

-          Silt. Silt particles are medium-sized. They feel soft, silky, and just like the flour used for baking.

-          Clay. Clay particles are fine and the smallest in size. They tend to clump together, feel sticky and is hard to squeeze.

10.   How to grow plant well? To grow  well, plants need water, minerals, air, and a,chorage to the ground.

11.   Occurances of day and night. The sun rises in the morning and sets in the evening. Appears it its highest around noon, but at night we cannot see it. The sun is like moving. Actually is not. Rather, it is the earth that spins and makes the sun appear to move across the sky.

12.   How long the earth’s rotation and revolution duration? The time  it takes  for the earth to make one complete rotation is 24 hours. And each revolution of the earth around the sun takes about 365 days.

13.   What is rotation? Rotation is the spinning action of the earth and makes the sun appear to move across the sky.

14.   Revolution of the moon around the earth (phases of lunar cycle).

The moon takes about 28 days, or about a month, to orbit the earth.

15.   What are the some of the objects that make up the Solar system?  The  sun, the moon, planets, comets, asteroids, and the meteoroids.

16.   The planets, moon, sun, comets, asteroids, meteoroids.

-          The sun is the central objects in the solar system. The sun is the closest star to the earth. The sun is also the largest object in the solar system.

-          The moon moves around the earth in a circular path. It does not produce light on its own. We can see it at night because it reflects light from the sun

-          The earth is a planet. Planets do not give out light of their own. The earth is the only planet that is known to support life. This is because water is present on the surface of the earth. Also, the earth is neither too close nor too far away from the sun. So, the temperature on the earth is just right for living things to survive. There are 8 planets. They are mercury, Venus, earth, mars, Jupiter, Saturn, Uranus, Neptune.

-          Comets are made up of ice, gas, dust, and small rocky particles. When a comet is far away from the sun, it can hardly be seen from the earth. When the comet is close enough to the sun, heat from the sun causes the ice in the comet to change into gas directly.

-          Asteroids are irregular shapes pieces of rock and metal that exist in spaces. They are smaller than planets.

-          Meteoroids are small pieces of rocks  in space that have broken off from a planet or an asteroid. Meteor that reach the earth’s surface are called meteorites.

17.   How are planets arranged in the solar system and how do they move around the Sun? all the planets in the solar system revolve or go around the sun in specific elliptical paths known as orbits. When planets revolve around the sun, we say they are orbiting the sun.

18.   How phases of lunar cycle happen? During each lunar cycle, different parts of the moon are lit by the sun. this is because the moon is at a different position relative to the sun and the earth in each phase of the cycle. The shape of the moon that we see from the earth depends on how much of the lighted part of the mo on is facing the earth.