Science Week 9, Level G ,

Explanation
Objects that have opposite charges attract each other because positive and negative charges are attracted to each other due to the fundamental nature of electric forces. The positive charge has an excess of protons and the negative charge has an excess of electrons. These opposite charges create an electric field that pulls the objects towards each other, resulting in attraction.

Explanation
Similar charges repel each other because they have an excess of the same type of charge. In this case, both objects have negative charges. Since like charges repel, the two negatively charged objects will repel each other. This can be explained by the fact that the negative charges on the objects create an electric field that pushes them apart, resulting in a repulsive force between them.

Explanation
A charged object can attract an uncharged object because opposite charges attract each other. When an object is charged, it has an excess or deficit of electrons. This creates an electric field around the charged object. In the case of an uncharged object, it has an equal number of protons and electrons, resulting in a neutral charge. The electric field of the charged object interacts with the neutral object, causing a redistribution of electrons. This redistribution creates an imbalance of charges, with the side of the neutral object closer to the charged object becoming oppositely charged. As a result, the charged object and the uncharged object attract each other due to the attraction between opposite charges.

Explanation
When an object becomes positively charged, its negative charges move towards another object. This happens because positive charges and negative charges attract each other. So, when negative charges move away from an object, it leaves behind a deficiency of negative charges, resulting in a net positive charge on the object.

Explanation
When you rub a balloon with a wool cloth, it gains electrons from the cloth and becomes negatively charged. On the other hand, when you rub a balloon with a plastic wrap, it loses electrons and becomes positively charged. Since opposite charges attract, the negatively charged balloon will be attracted to the positively charged balloon, causing them to attract each other.

Explanation
When you rub a ruler against your hair, the ruler gains negative charges and becomes negatively charged. The negatively charged ruler is able to attract the neutral bits of paper because charged objects always attract uncharged objects.

Explanation
Current electricity refers to the flow of electric charges, specifically the movement of negative charges through a conducting medium. In the context of a television, current electricity is essential for its proper functioning. The flow of electric charges enables the transmission of signals and the generation of the necessary electrical energy to power the various components of the television, such as the screen, speakers, and circuitry. Without current electricity, the television would not be able to operate and display images or produce sound.

Explanation
A conductor is a material that allows electric charges to move through it easily. Materials like copper, silver, steel, and tap water are good conductors of electricity because they have loosely bound electrons that are free to move. When a voltage is applied, these free electrons can easily flow, creating an electric current.

Explanation
An insulator is an object that restricts the flow of electric charges, making it difficult for them to move through the material. Materials like rubber, wood, and plastic are examples of insulators because they have high resistance to the flow of electric current. This means that electric charges cannot easily pass through these materials, preventing the movement of electricity.

Explanation
The inside of the electrical wire is made of copper, which is a good conductor of electricity. This allows the electric current to flow easily through the wire. The outside of the wire is made of plastic, which is an insulator. This insulating layer prevents any electric current from escaping the wire and also protects us from getting electrocuted when we touch the wire.

Explanation
A lamp or a light bulb converts electrical energy into light energy. When electricity passes through the filament of the bulb, it heats up and emits photons, which are particles of light. These photons then travel outwards, illuminating the surroundings and producing visible light. This conversion of electrical energy into light energy allows us to have artificial lighting in our homes and other places.

Explanation
A radio speaker or a buzzer converts the electrical energy into sound energy. When an electrical current is passed through the speaker or buzzer, it causes a diaphragm or a vibrating element to move back and forth rapidly. This movement creates sound waves, which travel through the air and reach our ears as sound energy. Therefore, the correct answer is sound.

Explanation
When the alarm rings, the electrical energy is converted into sound energy. The sound produced by the alarm clock is a result of the electrical energy being transformed into vibrations in the speaker, which in turn creates sound waves. Additionally, the screen of the alarm clock converts electrical energy into light energy. This is achieved through the use of LED or LCD technology, where electrical energy is used to power the backlight, causing it to emit light and illuminate the screen.

Explanation
A toaster converts electrical energy into thermal energy. When electricity flows through the toaster's heating elements, it generates heat. This heat is then transferred to the bread or other food items placed in the toaster, causing them to become toasted or heated. Therefore, the toaster's primary function is to convert electrical energy into thermal energy to cook or heat food.

Explanation
The given answer is correct because energy is the capacity or ability to cause a change. It can exist in various forms such as light energy, electric energy, sound energy, and chemical energy. These different forms of energy can be converted from one to another and are responsible for the various changes and processes that occur in the world.

Explanation
The main source of energy that humans need to do their daily activities is chemical energy in food. Chemical energy is stored in the bonds of molecules and is released through chemical reactions, such as the breakdown of carbohydrates, fats, and proteins during digestion. When these molecules are broken down, the energy stored in their bonds is released and can be used by the body to perform various activities, such as walking, talking, and even thinking. Therefore, chemical energy in food is essential for providing the energy required for human daily activities.