Which of the following is a characteristic of transparent materials?

They allow light to pass through easily.

They allow only some light to pass through.

What is the main difference between luminous and non-luminous bodies?

Luminous bodies emit their own light.

Non-luminous bodies shine brightly.

Luminous bodies reflect light only.

Non-luminous bodies emit light.

What is a property of incandescent light sources?

They produce light by heating a filament.

They reflect light from other sources.

They use chemical reactions to create light.

They emit light through gas discharge.

Which of the following describes a translucent material?

It allows some light to pass through, but not detailed images.

It blocks all light completely.

It allows all light to pass through clearly.

What is the definition of light?

Light is a form of energy that travels in waves.

What characteristic distinguishes fluorescent lights from incandescent lights?

Fluorescent lights use gases to produce light.

Fluorescent lights use filaments.

Fluorescent lights are always yellow.

Fluorescent lights generate heat.

Definition of light, property of light, sources of light, luminous body, opaque, transparent, translucent, incandescent, flourecent

• Agriculture is growing of crops and keeping of animals. • People who practice agriculture are called farmers. • Agriculture is very important to the family. Benefits to the family • It provides food. • It provides money. • Agriculture gives us medicine. • It provides jobs. • Agriculture gives us transport and power. • It helps most families become self sufficient. • Farm tools are instruments used on farms to make work easier. • They are usually handheld and are used frequently when practicing agricultural activities. • Farm tools are light in weight, easy to handle and are suited to the strength of the farmer Name of tool Picture Use Watering can For fine watering of seed beds bucket Carrying manure, fertilizer,seed and ripe crops Name of tool Picture Use Sickle Cutting grass and harvesting of cereals like rice and wheat Slasher Cutting down tall grass and weeds USES OF FARM TOOLS Name of tool Picture Use Garden trowel Transplanting seedlings and making planting holes Hand fork Shallow cultivation of soil Aerating the soil USES OF FARM TOOLS Name of tool Picture Use Shovel Loading and offloading soil or manure into a wheelbarrow, scotch cart or truck Spade Digging and turning over of moist soil USES OF FARM TOOLS Name of tool Picture Use Garden fork Loosening and turn soil Garden line Marking straight ridges and garden beds USES OF FARM TOOLS Name of tool Picture Use wheelbarrow Moving items around the farm Items such as soil, mulch, animal feed. Etc Knapsack sprayer Spraying pesticides and herbicides Spraying fertilizers on crops. • An inventory is a record of the things that you have. • This is a list of tools issued out and tools received back and from whom Inventory of farm tools Inventory record sheets Created by Date Name of tool Sheet Tool numbenumber Description r Location Quantity Spade 1/15 Black,wooden handle Store room 2 SAFETY IN AGRICULTURE • Agricultural activities can be dangerous. • Hazards involved results in injury, disability and death of people and animals. • The hazards are usually caused by physical injury and chemical poisoning. Common hazards in Agriculture 1. physical injury These include: • Injury caused by accidents during use of farm tools, equipment and machinery. • Misuse and improper storage of farm tools and equipment. • Being kicked by animals. • Drowning in farm pond, pool or dam. Common hazards in Agriculture 2 . Chemical poisoning These include: • Spraying without protective clothing. • Eating or smoking when spraying chemicals. • Dumping toxic chemical left overs on land and in water. • Eating agriculture produces without prior permission from adults. • Pesticides, herbicides and fertilizers pollute water sources and kill animals. Chemical poisoning Ways of preventing common agricultural hazards 1. Wear protective clothing such as gloves, gumboots, respirator, hat and overalls. 2. Do not eat, drink or smoke when spraying. 3. Dispose off all chemical remains safely. 4. Bury or burn empty chemical containers and chemical left overs. 5. Wash thoroughly with running water and soap after using chemicals. 6. Do not spray during windy days. 7. Handle tools the right way. 8. Fence farm ponds and dams. Ways of preventing common agricultural hazards Climate and Landuse Seasons of Zimbabwe Seasons of Zimbabwe Definition of terms • A season is a time of the year with almost the same weather patterns. • Weather is the state of the atmosphere at a particular time at a particular place. • it is the daily condition of air around us. • Seasons are determined by rainfall and temperature. Seasons of Zimbabwe • There are four seasons in Zimbabwe , which are: 1.The rain season 2.Post rain season 3.Cool dry season 4.Hot dry season Seasons of Zimbabwe 1.The rain season ( summer) • It is also called the hot- wet season. • The season begins in mid November to mid March. • The period is rainy and hot. • Dams and rivers fill up. Seasons of Zimbabwe 2 . The post rain season ( autumn ) • It starts mid March – May • The days are bright and sunny. • The leaves change from green to red, orange, yellow or brown before falling. • In addition, there is less sunlight because the days are shorter. • It is the harvesting period of most crops. Seasons of Zimbabwe 3. The cold dry season ( winter ) • It begins mid May – mid August • The mornings, evenings and nights are very cold. • Has short days and long nights. Seasons of Zimbabwe 4 . The hot season (spring ) • It begins mid August – mid November. • The days are very hot with cool nights. • A season for trees to develop new shoots. Summer Activities Agricultural activities done during the rain season includes: • Ploughing and planting of summer crops for example maize, cotton. • Weeding • Pest and disease control • Applying fertilizers. • Weekly dipping of animals because ticks, lice and mites would be many. • Harvesting of summer crops • Preparing fireguards. A fireguard is a fire break. • Beginning of the planting of wheat, barley and oats. Winter Activities • Planting of winter crops such as wheat, barley and oats. • Harvesting and selling of summer crops continues. • Constructing frost barriers for frost sensitive crops such as tomatoes. • Vaccinating animals against blackleg. • Supplementary feeding of grazing animals. • Dosing of animals to kill internal parasites. Spring Activities • Shelling and threshing of grain crops. • Dry planting of summer crops. • Carrying manure to fields. • Ploughing and harrowing. • Making planting holes Soil Components •Soil is made up of 4 components: 1)Mineral matter 2)Organic matter 3)Soil water 4)Soil air

What is Electric Force? Electric force is just one of many types of forces in the world of physics. Forces are how and why things move, and can be explained by Newton's Laws of Motion. On the smallest scale, electric force is the resulting interaction between two charged particles. These charges can be either positive or negative. Larger objects can be charged by having an abundance of either of these particles, and therefore can create an electric force on a larger scale. Electric force is the reason why hair will sometimes stand up on its own and is also why we have electricity, allowing us to live in the modern world with lights and technology. Even out in nature electric force is present, as electric force causes lightning to strike. Electric force is fundamental to our everyday way of living. Reviewing Newton's Laws of Motion Newton's Laws of motion are the basic principles or ground rules that are applied all across physics. They describe how objects move and can be used to describe the interaction of charges. They are the following: An object in motion will stay in motion unless an external force is applied The force exerted on an object is equal to the mass times the acceleration of the object. ( ) Every force has an equal and opposite force Newton's laws explain how and why charged particles move. Since there is a force involved (e.g. electric force), particles will move around, which is explained by the first law. The second law describes how acceleration of charges can be calculated once the electric force is known. The third law explains how attractive and repulsive forces between charged objects are equal and opposite. Electric Force Examples and Types of Charge As previously mentioned, there are only two types of charges; positive and negative. Two like charges will repel (or move away from) each other, and two opposite charges will attract (or move towards) each other. In other words, two positive or two negative charges will repel, while a positive and a negative charge will attract. Opposite charges will attract while like charges will repel. Attraction versus Repelling Forces Notice how the forces acting upon each other are equal and opposite, as Newton's third law states. Both charges are exerting forces onto each other. Charges in Atoms An atom is made up of three types of particles; protons, neutrons, and electrons. Protons have a positive charge, neutrons have no charge, and electrons have a negative charge. There are no positive or negative charges smaller than protons and electrons. Objects on a larger scale result in an overall positive or negative charged due to an uneven distribution of protons to electrons. An atom consisting of more protons than electrons would be considered positive, and an atom with more electrons than protons would be considered negative. Protons are held close to the nucleus and are tightly bound to an atom, so it's difficult for protons to escape an atom. Electrons, on the other hand, are much further away from the nucleus of an atom. This makes it much easier for them to be removed from an atom. Electrons can leave or join atoms, making them positive or negative depending on the amount of protons. Similarly, for the bigger picture, overall materials and objects with more electrons than protons would be considered negative, and vice versa. Electric Force Examples Hair standing up: When hair is brushed, the hairbrush can strip electrons from hair strands, resulting in the hair being positively charged. This addition of electrons to the hairbrush in turn makes the hairbrush negatively charged. Since the hair is now positively charged, and like forces repel, hair strands will move away from each other, resulting in the hair standing up. Current electricity: All of our everyday technology is powered through current electricity, which is the consistent flow of electrons through conductive materials. This flow is caused by the electric force, as the electrons flow from a negative source to a positive source. Lightning: During a storm, it is common for an abundance of electrons to build up on the bottom of a cloud, making that part of the cloud negatively charged. Positive charges in the ground start to gather on the surface or even on tall objects such as trees as they are attracted towards the negatively charged undersides of clouds. Lightning strikes as a result of these charges becoming extremely built up. Lightning is caused by electric force Lightning Electric Force Equation: Coulomb's Law The magnitude of the electric force, or the amount of force in which objects repel or attract, depends on the distance between the two charged objects and the amount of charge each object carries. The electric force is stronger the closer together the two charges are, and weaker as the two charges move apart. Electric force is also stronger with more charge, and weaker with less charge. This effect on electric force is predictable, and is known as Coulomb's Law. It can be calculated using a mathematical equation, and the resulting magnitude of electric force is measured in Newtons. Coulomb's Law Electric force can be calculated using the following equation known as Coulomb's Law: In this equation, F is the electric force measured in newtons, K is a constant known as the electrostatic constant, and are charges one and two measured in coulombs, and is the radial distance in meters between the two charges. Since the distance is squared and on the denominator, the electric force drops off exponentially as charges move away from each other. This means that the Electric force is inversely proportional to distance. As charges move away from each other, the electric force between them gets smaller and smaller, until the force is negligible. The amount of charges are in the numerator of this equation, making the magnitude of the force larger with more charge. This means that the force is directly proportional to the amount of charge. When the charges are smaller, the amount of force will be smaller. When there is a lot of charge, the force will be much greater. When calculating the electric force using Coulomb's law, the resulting answer only gives the magnitude of the force and not the direction. In order to know the direction, you must know the types of charges. Once again, like forces repel, and unlike forces attract. It helps to draw a visual representation, or a free-body diagram, of the charges and forces acting upon them in order to understand the resulting force direction. Electric Field versus Electric Force An electric field is a direct result of an electric force. Its pure definition is electric force per unit charge, and can be thought of as a mapping of the force vectors. An electric field is present anytime there is an electric force. Therefore, when there are two or more charged particles, there is a surrounding electric field. The direction of the electric field is the direction a positive charge would flow if it were placed within the field. The electric field moves out from a positive charge and goes into a negative charge. Particles with unlike charges move towards each other, and their corresponding electric field lines move out from the positive charge and into the negative charge. The strength of the force at any given point can be seen through the spacing of the electric field lines. The electric force is strongest where the electric field lines are closest together, and weaker as these lines move apart. Like Coulomb's law expresses, electric field lines show how the electric force is strongest with a minimum distance between the two charges. Unlike charges will result in a repelling force, and the resulting electric field is a visual representation of this effect. Electric fields of two positive charges have the electric field moving out away from both of them. As with two negative charges, the field lines move in towards each negative. Lesson Summary An electric force is created when there are two or more charged particles or objects. These charges can be either positive or negative. Like charges will attract (move towards each other) while unlike charges will repel (move away from each other). As Newton's third law suggests, the forces acting upon each other are both equal and opposite. Electrons and protons within an atom are the two smallest types of charges there are. Electrons carry a negative charge while protons carry a positive charge. Electrons can be easily removed or added to atoms, making the overall charge positive or negative. Objects with more electrons than protons are negatively charged. Electric force is strengthened with increased charge and a shorter distance between the charges. This effect is known as Coulomb's law and can be calculated with the Coulomb's law equation. The magnitude of the force is measured in Newtons, and the direction can be determined by knowing whether the charges are attracting or repelling each other. An electric field is present wherever there is an electric force. The direction of this electric field is the direction a positive charge would flow if it where to be dropped in the field, which is from the positive to the negative.

Definition of Empire

Definition of Computer Games: A computer game is a game that is played on a computer. It is also played on a small portable piece of electronic equipment eg telephone or handset.

Definition of science, Biology and its branches

Definition of hardware

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