Practice Questions

<p>List two examples of how electric current is used in everyday life.</p>

<p>Define the term &#39;investigation&#39; in the context of science.</p>

<p>Recall two factors that can be changed during an experiment to see how a puri puffs up.</p>

<p>Classify the following materials as elements, compounds, or mixtures: oxygen, water, air, and salt (sodium chloride). Justify your classification for each material.</p>

<p>Compare and contrast the properties of solids, liquids, and gases in terms of the arrangement and movement of their particles.</p>

<p>Name the three states of matter based on the movement of particles.</p>

<p>Identify the main components of a mixture.</p>

<p>How does a vaccine help the body fight infections? Explain the process involved in building immunity through vaccination.</p>

<p>Describe what happens to light rays when they reflect off a flat mirror.</p>

<p>Summarize the relationship between living organisms and their environments.</p>

<p>A cyclist applies a force of $50$ N to the pedals of a bicycle. If the area of each pedal is $0.02$ m², calculate the pressure exerted on each pedal. Explain how pressure and force are related in this scenario.</p>

<p>Explain how the phases of the Moon occur and relate them to the relative positions of the Earth, Moon, and Sun. Include a diagram.</p>

<p>Describe how a cyclone is formed. Relate pressure differences and air movement in your explanation.</p>

<p>Describe how scientists observe the phases of the Moon.</p>

<p>Explain how understanding forces helps explain why a ball thrown up in the air falls back to the ground.</p>

<p>A sugar cube is added to a glass of water and stirred. Analyze what happens at the particle level and explain why the sugar cube eventually disappears.</p>

<p>A mirror is used to view an object. Analyze how the type of mirror (plane, concave, or convex) affects the characteristics of the image formed (size, orientation, and whether it is real or virtual).</p>

<p>A lens forms a real, inverted image of an object. Analyze the characteristics of the lens (concave or convex) and the possible positions of the object relative to the lens.</p>

<p>A circuit contains a $6$ V battery and a resistor with a resistance of $2$ ohms. Calculate the current flowing through the circuit. If the resistance is doubled, how does the current change?</p>

<p>Describe how air pressure differences lead to wind.</p>

<p>A car accelerates from rest to a speed of $20$ m/s in $5$ seconds. Calculate the average acceleration of the car. Also, describe what this acceleration means in terms of the car&#39;s motion.</p>

<p>Two identical metal balls are dropped from the same height. One is dropped in air and the other in water. Analyze and explain which ball will reach the ground/bottom first and why.</p>

<p>Analyze the potential consequences of deforestation on ecosystems and climate change. Explain how deforestation contributes to these problems.</p>

<p>Explain why the Earth is considered &#39;just right&#39; for life.</p>

<p>Explain the difference between elements, compounds, and mixtures.</p>

<p>Describe one way human activities can affect the Earth&#39;s climate.</p>

<p>A student observes that a metal spoon feels colder than a wooden spoon when both are at room temperature. Analyze this observation and explain why this occurs based on the concept of heat transfer.</p>

<p>Explain how the root and kite symbols relate to scientific investigation, according to the text.</p>

<p>A ball is thrown vertically upwards with an initial velocity of $15$ m/s. Calculate the maximum height reached by the ball. (Assume $g = 9.8$ m/s²)</p>

<p>Summarize the steps involved in conducting a scientific experiment, using the puri example.</p>