End Of Year Science

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A hypothesis is an educated guess or a proposed explanation based on limited evidence or prior knowledge. It is a statement that can be tested through observation or experimentation. In the scientific method, a hypothesis is formulated before conducting any experiments or gathering data. It serves as a starting point for further investigation and helps researchers make predictions about the outcome of their study. Therefore, a hypothesis is the most appropriate option as an educated guess among the given choices.

The student plans to make a closed circuit to make the light bulb glow. In order to achieve this, they need to use conductive materials that can allow the flow of electric current. Copper penny, metal spoon, and iron nail are all conductive materials that can be used to complete the circuit. However, a plastic comb is an insulator and does not allow the flow of electric current, so it cannot be used to make the light bulb glow.

If the fox is taken out of the cycle, there would be an increase in the mouse population. This is because the fox is a predator of mice, and without the presence of foxes, the mouse population would not be controlled, leading to an increase in their numbers.

Matter is the correct answer because it refers to anything that has mass and occupies space. Matter can exist in different forms such as solid, liquid, or gas. It includes all substances and materials that make up the physical world around us, including living organisms. Evaporation, cycle, and weight do not fully encompass the definition of matter.

When an insect produces waves in the air, these air vibrations can result in the production of sound. Sound is a form of energy that travels through waves in the air and can be perceived by our ears. Therefore, the correct answer is sound.

When sand is added to water, it will sink to the bottom. This is because sand is denser than water, causing it to be pulled down by gravity. The particles of sand are too heavy to remain suspended in the water, so they settle at the bottom. Dissolving refers to a substance becoming incorporated into a liquid at a molecular level, which does not occur with sand and water. Disappearing or floating to the top are also not accurate as they do not align with the behavior of sand in water.

The best way to separate iron fillings and sand is by using a magnet. Iron fillings are magnetic, so when a magnet is passed over the mixture, the iron fillings will be attracted to the magnet and can be easily separated from the sand. Using a filter or a funnel would not be effective in this case as both substances do not have significant size differences to be separated by filtration or decantation. Using hands would be impractical and time-consuming.

The moon appears to glow because it reflects the Sun's light. As the Sun shines its light onto the moon, the moon's surface reflects that light back towards Earth, creating the appearance of a glowing moon in the night sky. This reflection is what allows us to see the moon even when it is not directly illuminated by the Sun.

The temperature at which they freeze will be the same for both cups of water because the freezing point of water is a constant value regardless of the volume or mass of the water.

Talking is not an inherited trait because it is a learned behavior that is acquired through social interaction and language acquisition. While hair color, shape of nose, and freckles are all determined by genetic factors and can be inherited from parents, talking is a skill that is developed through exposure to language and communication.

This photo is a good example of erosion because it shows the gradual wearing away and removal of the land or rock surface. The visible patterns of sediment deposition and the smooth, sculpted features indicate the action of water or wind eroding the landscape over time. The presence of sediment and the absence of any signs of recycling or inexhaustible resources further support the explanation of erosion.

The correct answer is the Earth rotating on its axis. Day and night occur because as the Earth rotates, different parts of it are exposed to the Sun's light. When a particular area is facing the Sun, it experiences daylight, while the opposite side experiences darkness, resulting in night. This rotation creates the cycle of day and night that we observe on Earth.

When Ms. Gustavus turned on the heater in her car, the warm air inside the car came into contact with the cold windows. This temperature difference caused the moisture in the air to condense on the windows, leading to the fogging up.

If you went to the moon, your weight would change. This is because weight is determined by the force of gravity acting on an object, and the moon has much less gravity than Earth. Therefore, your weight would be significantly reduced on the moon compared to what it is on Earth.

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The correct answer is "The plant" because a producer is an organism that can make its own food through photosynthesis. Plants are able to convert sunlight into energy through photosynthesis, making them producers in the food chain.

Over time, wind and rain can cause sharp rough mountains to become rounded. The constant erosion caused by wind-blown particles and the erosive force of rainwater can wear down the sharp edges and surfaces of mountains, smoothing them out and creating a more rounded appearance. This process, known as weathering, gradually breaks down the rock material and reshapes the mountain landscape.

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The correct answer is 52 weeks because it takes the Earth approximately 365.25 days to complete one revolution around the Sun. Since there are 52 weeks in a year, this means that it takes the Earth about 52 weeks to complete its orbit.

Fossil fuels, such as coal, oil, and natural gas, formed over a long period of time due to the burial of organic matter, specifically the remains of plants and animals, in the ground. This organic matter was subjected to heat and pressure over millions of years, which caused the decomposition and transformation of the organic material into fossil fuels. The process of burial and subsequent geological processes, such as sedimentation and compaction, contributed to the formation of fossil fuels.

If the volume of an object is greater than its mass, it means that the object is less dense than water. Since objects that are less dense than water tend to float, the correct answer is "Float in water".

Volcanoes can build up land by adding lava to the Earth's surface. When a volcano erupts, molten rock called lava is released onto the surface. As the lava cools and solidifies, it forms new land. Over time, repeated volcanic eruptions can lead to the formation of mountains, islands, and other landforms. This process is known as volcanic activity and is responsible for the creation of many land features on Earth.

Glasses are an example of refraction because they have a curved surface that causes light to bend as it passes through. This bending of light is known as refraction. When light enters the glass, it changes speed and direction, causing the image to appear closer or larger than it actually is. This phenomenon is commonly observed when wearing glasses, as they help to correct vision by refracting light in a way that allows for clearer focus.

Resources do not cause weathering, erosion, and deposition. Weathering refers to the breaking down of rocks into smaller pieces, erosion refers to the movement of these broken pieces, and deposition refers to the laying down of these pieces in a new location. Resources, such as minerals and fossil fuels, are not directly involved in these processes. Weathering, erosion, and deposition are mainly caused by natural forces like gravity, wind, glaciers, and water.

In an investigation, it is recommended to have only one variable. This is because having multiple variables can make it difficult to determine the cause and effect relationship between the variables. By focusing on a single variable, it becomes easier to analyze and interpret the data, leading to more accurate and reliable results. Additionally, having multiple variables can increase the complexity of the investigation and make it harder to control other factors that may influence the outcome. Therefore, it is best to limit the investigation to one variable.

Soil is considered a renewable resource because it can be replenished over time through natural processes such as decomposition of organic matter and weathering of rocks. It is a vital component for plant growth and agriculture, and can be managed sustainably through practices like crop rotation and organic farming. Unlike wind, coal, and minerals, which are non-renewable resources that are finite in supply and take millions of years to form, soil can be continuously regenerated with proper conservation and management techniques.

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