Jan2x - Science 3 [3rd Quarterly Exam]

Whispering to your classmate produces a soft sound because it involves speaking in a low volume and using gentle vocalization. This results in a sound that is not loud or harsh, but rather quiet and gentle.

Water is essential for photosynthesis, the process by which plants convert sunlight into energy. During photosynthesis, water is absorbed by plant roots and transported to the leaves, where it combines with carbon dioxide and sunlight to produce glucose and oxygen. Glucose is the primary source of energy for plants, and it is used to fuel their growth and development. Without water, plants would not be able to produce the necessary food to survive and thrive.

The correct answer is land because the question is asking about the places on Earth that appear green, which is typically due to the presence of plants. While the atmosphere and water can also appear green in certain circumstances, the most common and widespread occurrence of green on Earth is on land, where plants grow.

Earth gets light from the sun. The sun is a star located at the center of the solar system and it emits light and heat energy through a process called nuclear fusion. This light energy travels through space and reaches the Earth, providing us with warmth, light, and energy for various natural processes such as photosynthesis. The sun is essential for the existence of life on Earth and plays a crucial role in maintaining the planet's climate and ecosystems.

Worms do not produce sound because they lack vocal cords or any other sound-producing structures. Unlike alarm clocks and chickens, worms do not have the ability to make audible noises.

The correct answer is ocean because it is the largest water body on Earth, covering about 71% of the planet's surface. Oceans are vast and deep, containing saltwater and supporting a wide variety of marine life. They play a crucial role in regulating the Earth's climate, providing oxygen, and serving as a major transportation route for trade and commerce.

Heat is the correct answer because it is a form of energy that is responsible for keeping people warm. When an object or substance has a higher temperature than its surroundings, it transfers heat to its surroundings, resulting in a warming effect. Heat can be produced by various sources such as fire, the sun, or even electrical appliances. It is an essential form of energy for maintaining body temperature and ensuring comfort in cold environments.

The question is asking for the correct term that describes a push or a pull. The term that fits this description is "force". A force can either push or pull an object, causing it to move or change its state of motion. Therefore, force is the correct answer.

The correct answer is "ball" because the Earth is an oblate spheroid, meaning it is mostly spherical but slightly flattened at the poles and bulging at the equator. This shape is a result of the Earth's rotation, which causes the equatorial region to experience a centrifugal force that pushes outwards, while the polar regions are compressed.

Pushing means applying force to an object in a direction away from oneself. When you push an object, you exert force on it to move it away from you. This can be done by using your hands, body, or any other means to apply pressure in the opposite direction of the object's current position.

The sun gives off both heat and light energy. It is a massive ball of hot gases that undergo nuclear fusion, which releases a tremendous amount of energy in the form of heat and light. This energy is radiated outwards and reaches the Earth, providing us with warmth and enabling photosynthesis, which is essential for all life on Earth.

Sound is produced when a person sings or hums. This is because singing or humming involves the vibration of vocal cords, which creates sound waves. These sound waves travel through the air and reach our ears, allowing us to perceive the sound. Therefore, sound is the correct answer in this context.

A dog can move by itself because it has the ability to walk and run using its four legs. Unlike a plant, which is rooted in the ground and cannot move, and a table, which is an inanimate object and does not have the ability to move on its own, a dog has the physical capability to move independently. Dogs are known for their agility and mobility, allowing them to navigate their surroundings and explore their environment.

An escalator is run by electricity as it requires a power source to operate. Electricity powers the motor that drives the escalator's continuous movement, allowing people to move effortlessly between different levels of a building. Wind and water are not typically used to power escalators, making electricity the most logical and practical choice for this type of transportation device.

A candle produces light because it contains a wick made of a flammable material, such as cotton, which when lit creates a flame. The flame then melts the wax surrounding the wick, which vaporizes and combusts, releasing energy in the form of light and heat. This process is known as combustion and is the reason why a candle produces light.

The clapping of hands produces sound because it involves the collision of two surfaces, which creates vibrations in the air that are perceived as sound waves. In contrast, a pencil on the table or a notebook in a bag do not produce sound on their own as they do not involve any collision or movement that can generate vibrations in the air.

The movement described in the question is the motion of driving a nail into the floor with a hammer. When you perform this action, you typically raise the hammer above your head and then bring it down forcefully onto the nail, causing an up and down motion. Therefore, the correct answer is up and down.

When you clap your hands, the energy produced is in the form of sound. Sound is a type of energy that travels in waves through a medium, such as air or water. When you clap your hands, the motion creates vibrations in the air molecules, which then propagate as sound waves. These waves reach our ears and are interpreted by our brain as sound. Therefore, the correct answer is sound.

Earth is considered a planet because it meets the criteria to be classified as one. It orbits around the Sun, has sufficient mass to be nearly spherical in shape, and has cleared its orbit of other debris. Additionally, Earth has a solid surface, an atmosphere, and supports life. Therefore, it is categorized as a planet in our solar system.

Throwing a ball involves exerting force on the ball in order to make it move away from the person. This action requires the person to push the ball with their hand or arm in a forward motion. On the other hand, opening a drawer involves pulling it towards oneself, and lifting a ball involves raising it upwards. Therefore, throwing a ball is the only option that demonstrates pushing.

Using sunglasses when walking under the sun is a good practice because it helps protect your eyes from harmful ultraviolet (UV) rays. UV rays can cause damage to the eyes, leading to conditions such as cataracts, macular degeneration, and photokeratitis. Wearing sunglasses with UV protection can help prevent these risks and maintain good eye health.

A landform that is higher than a hill is a mountain. Hills are smaller and less steep compared to mountains, which are larger and have higher elevations. Mountains are typically formed through geological processes such as tectonic activity or volcanic eruptions. They are characterized by their towering peaks, rugged terrain, and often serve as natural boundaries between regions.

A water form that is bigger than a pond and surrounded by land is referred to as a lake. A lake is a large body of water that is usually freshwater and is completely enclosed by land. It is larger than a pond and can vary in size and depth. Lakes are formed through various processes such as tectonic activity, glaciation, or volcanic activity. They play a crucial role in ecosystems, providing habitats for various plants and animals, as well as serving as a source of freshwater for human use.

The person dusting a furniture shows motion because they are actively engaged in an action, specifically the act of dusting. The other options, paper on a table and a person looking in the mirror, do not involve any visible movement or action.

The correct answer is atmosphere. The part that appears white around Earth is the atmosphere. The atmosphere is a layer of gases that surround the planet and is responsible for trapping heat, protecting us from harmful radiation, and providing the air we breathe. It appears white because of the scattering of sunlight by the molecules in the atmosphere, which makes it look bright and hazy when viewed from space.

To protect your ears from loud sounds, it is advisable to stay away from noisy places. Exposure to loud noises can cause damage to the delicate structures in the ear, leading to hearing loss or other auditory problems. By avoiding loud environments, you can minimize the risk of such damage and maintain the health of your ears.

The correct answer is sun's heat because heat from the sun causes the water in wet clothes to evaporate, leading to the drying process. The sun's heat provides the necessary energy to convert liquid water into water vapor, which then escapes into the air. Without the heat from the sun, wet clothes would take much longer to dry, if they dry at all.

Sound is produced when things vibrate. When an object vibrates, it creates waves of pressure in the surrounding air or other medium. These waves travel through the medium and reach our ears, where they are interpreted as sound. Therefore, sound is the correct answer because it is directly linked to the vibration of objects.

Burning wood can be a source of heat energy because when wood is burned, it undergoes a chemical reaction called combustion. During combustion, the energy stored in the chemical bonds of the wood is released in the form of heat and light. This heat energy can be utilized for various purposes such as cooking, heating homes, or generating electricity. Therefore, burning wood is a viable source of heat energy.

The force used to get a book from a bag is a pulling force. This involves applying a force in the direction opposite to the book's movement, causing it to come out of the bag. A pushing force would be applied in the same direction as the book's movement, which would not be effective in getting the book out. Sound is not relevant to the action of getting a book from a bag.

A hair dryer produces heat without light. Unlike a bulb or a lamp, the primary function of a hair dryer is to generate hot air for drying hair. While a bulb or a lamp produces both heat and light, a hair dryer is designed specifically for heat production without the emission of light.

Pull is the correct answer because it refers to the force that moves an object toward you. When you pull an object, you exert a force in the direction towards yourself, causing the object to move in that direction. This force can be applied by physically pulling on the object or by using a pulling mechanism such as a rope or a pulley system.

Push is the correct answer because when moving a baby on a stroller around the park, you need to exert a force in the forward direction to make the stroller move. Pushing the stroller applies a force opposite to the direction of motion, causing it to move forward. Gravity is not applicable in this context as it is a force that pulls objects towards the center of the Earth, and pull is not the force commonly used to move a stroller.

The falling rain is considered pleasant to the ears because it creates a soothing and calming sound. The gentle pitter-patter of raindrops hitting surfaces can create a relaxing and peaceful ambiance. This sound is often associated with tranquility and can be comforting to many people.

Motion refers to the change in the position of an object. It describes the movement of an object from one place to another. In physics, motion is typically measured in terms of distance, displacement, speed, velocity, and acceleration. It is a fundamental concept in understanding the behavior of objects in the physical world.

Stars are sources of light energy because they emit their own light through a process called nuclear fusion. In the core of a star, hydrogen atoms fuse together to form helium, releasing an enormous amount of energy in the form of light and heat. This light energy is then radiated outwards, allowing us to see the stars in the night sky. Unlike running water, sound, and wind, stars have the unique ability to generate and emit light energy.

Push is the correct answer because it is a force that moves an object away from you. When you push an object, you apply force in the direction away from yourself, causing the object to move in that direction. This is in contrast to pull, which is a force that moves an object towards you, and lift, which is a force that moves an object upwards.

Water freezing does not show the importance of heat because it is the absence of heat that causes water to freeze. When water loses heat, its molecules slow down and come closer together, forming a solid state. This process does not demonstrate the importance of heat, but rather the lack of it. On the other hand, plants growing and wet clothes drying both require heat as an essential factor for their respective processes to occur.

The sun gives off both heat and light. Heat is produced by the sun's intense nuclear reactions, which generate high temperatures. The light emitted by the sun is a result of these reactions as well, as it is produced by the energy released in the form of electromagnetic radiation. Therefore, the sun emits both heat and light as a result of its nuclear fusion processes.

A compost is made up of decaying materials and soil. Composting is a natural process where organic waste such as food scraps, yard waste, and other biodegradable materials are broken down by microorganisms into a nutrient-rich soil amendment called compost. Compost is beneficial for plants as it improves soil structure, retains moisture, and provides essential nutrients. Therefore, compost is the correct answer as it is directly related to the decomposition of organic matter and the creation of nutrient-rich soil.

The correct answer is water because water bodies such as oceans, lakes, and rivers appear blue due to the way they absorb and reflect sunlight. The molecules in water absorb colors in the red part of the spectrum, while reflecting colors in the blue part of the spectrum. This reflection of blue light is what gives water its characteristic blue appearance. Therefore, areas on Earth that appear blue are typically areas covered with water.

The air surrounding Earth is known as the atmosphere. It is a layer of gases that envelops the planet and is held in place by Earth's gravity. The atmosphere plays a crucial role in protecting life on Earth by absorbing harmful solar radiation, regulating temperature, and providing the oxygen necessary for respiration. It is composed primarily of nitrogen, oxygen, carbon dioxide, and trace amounts of other gases. The atmosphere also contains weather systems, such as clouds and storms, which contribute to Earth's climate and weather patterns.

The sun's light helps the skin make vitamin D. When the skin is exposed to sunlight, it triggers a chemical reaction that converts a form of cholesterol in the skin into vitamin D. This vitamin is essential for various bodily functions, including bone health and immune system regulation. Sunlight contains ultraviolet B (UVB) rays, which are responsible for this conversion process. Therefore, the sun's light is necessary for the production of vitamin D in the skin.

A landform that has a crater is a volcano. This is because volcanoes are formed when magma, gas, and other materials escape from beneath the Earth's surface through a vent or opening, creating a crater. The crater is typically located at the summit or top of the volcano and is formed due to the explosive release of volcanic materials. Volcanoes can vary in size and shape, but the presence of a crater is a defining characteristic of this landform.

Light is a form of energy that enables us to perceive and see objects in motion. It travels in the form of electromagnetic waves and interacts with our eyes, allowing us to detect and interpret the movement of objects. Unlike sound or running water, which are also forms of energy, light specifically refers to the energy that enables vision and the perception of motion.

Energy is required to make a push or a pull. Pushing or pulling an object requires the application of force, and force is a form of energy. Energy is the ability to do work or cause a change in an object's state or motion. In this case, the energy is being used to apply a force to move an object.

Putting them in a sack together with decaying garbage is the best way to dispose of garbage like empty bottles, old newspapers, tires, and used plastic containers. This method allows for proper segregation and containment of waste materials. By placing these items in a sack with decaying garbage, it helps prevent littering and ensures that the waste is properly managed. Additionally, this method can facilitate composting and decomposition of organic waste, contributing to environmental sustainability.

Earth is surrounded by water, which is evident from the fact that about 71% of the Earth's surface is covered by water bodies such as oceans, seas, lakes, and rivers. This water plays a crucial role in the Earth's climate, weather patterns, and the survival of various species. Additionally, the presence of water is also essential for supporting life on Earth, as it provides a habitat for numerous marine organisms and serves as a source of food and transportation for humans.

Composting is the process of converting organic waste materials, such as food scraps and yard trimmings, into nutrient-rich compost that can be used as a fertilizer for plants. This process involves the decomposition of organic matter by microorganisms, such as bacteria and fungi, in a controlled environment. Composting helps to reduce the amount of waste sent to landfills, improves soil health, and reduces the need for chemical fertilizers. Therefore, composting can be considered as the process of changing wastes into useful materials.

Pull is the correct answer because when raising a flag on a pole, you need to exert a force in the opposite direction of the flag's weight. By pulling the rope attached to the flag, you are able to lift it up the pole. Pushing or lifting would not be effective in this scenario.