Physics
What is the difference between speed and velocity?
Speed is how fast an object is moving, while velocity is speed with a direction.
What is an atom, and what are its main parts?
An atom is the smallest unit of matter, consisting of protons, neutrons, and electrons.
What is photosynthesis, and why is it important for plants?
Photosynthesis is the process by which plants use sunlight to convert carbon dioxide and water into glucose and oxygen. It is important because it provides energy for the plant and releases oxygen into the atmosphere.
What causes earthquakes to happen?
Earthquakes occur when tectonic plates in the Earth's crust shift or collide, releasing energy as seismic waves.
A force of 50 newtons is applied to push a box across a surface for a distance of 4 meters. How much work is done?
Work = Force × Distance = 50 N × 4 m = 200 J (joules).
State Newton's third law of motion in simple terms.
For every action, there is an equal and opposite reaction.
What is the pH scale used for, and what does it measure?
The pH scale measures how acidic or basic a substance is, ranging from 0 (acidic) to 14 (basic).
What is the primary function of white blood cells in the immune system, and how do they protect the body against infections?
White blood cells help defend the body against infections by identifying, attacking, and destroying harmful pathogens like bacteria and viruses. They do this through engulfing pathogens and producing antibodies.
Why are rainforests important to the Earth's environment?
Rainforests produce oxygen, absorb carbon dioxide, and support biodiversity by providing habitats for many species.
What is the greenhouse effect, and how does it contribute to maintaining Earth’s temperature?
The greenhouse effect is the process where gases in Earth’s atmosphere trap heat from the sun, keeping the planet warm. It is essential for maintaining a temperature that supports life, but an excess of greenhouse gases can lead to global warming.
What is the formula to calculate the speed of an object?
Speed = Distance ÷ Time
What happens when you mix an acid and a base?
When you mix an acid and a base, they neutralize each other, often forming water and a salt.
What are chromosomes, and where are they found in a cell?
Chromosomes are structures made of DNA that contain genetic information. They are found in the nucleus of a cell.
What is the main source of energy for the water cycle?
The sun is the main source of energy for the water cycle, causing water to evaporate and circulate through the atmosphere.
If an object weighs 50 N on Earth (where the gravitational acceleration is about 10 m/s²), what would its mass be on the Moon where gravity is about 1/6th of Earth’s gravity?
Mass = Weight ÷ Earth’s gravity = 50 N ÷ 10 m/s² ≈ 5 kg. The mass remains the same regardless of location, so it is approximately 5 kg on the Moon as well.
What is kinetic energy, and how is it different from potential energy?
Kinetic energy is the energy of motion, while potential energy is stored energy based on an object's position.
What subatomic particles are responsible for forming chemical bonds between atoms? Give examples of how they do it.
Electrons in the outermost shell (valence electrons) are involved in forming chemical bonds, such as covalent or ionic bonds, by being shared or transferred between atoms.
How do vaccines help the immune system fight off specific diseases?
Vaccines introduce a harmless form of a pathogen or its antigens, stimulating the immune system to produce antibodies and memory cells that recognize and fight the actual pathogen if encountered later.
How do coral reefs benefit marine ecosystems, and what threats are they currently facing?
Coral reefs provide habitat and food for many marine species, protect coastlines, and support biodiversity. They face threats like coral bleaching, pollution, and ocean acidification.
If a substance has a density of 8 g/cm³ and you have a 2 cm³ piece of it, what is its mass?
Mass = Density × Volume = 8 g/cm³ × 2 cm³ = 16 g.
Why does sound travel faster in solids than in gases?
Sound travels faster in solids because the particles are more closely packed, allowing the vibrations to transfer more quickly.
What is a mole in chemistry, and why is it used to measure chemical quantities?
A mole is a unit used to measure the amount of a substance. It represents Avogadro's number, which is 6.022 × 10²³ particles (atoms, molecules, or ions). It allows chemists to relate the mass of a substance to the number of particles it contains.
What is the role of mitochondria in cellular respiration?
Mitochondria are organelles that generate energy for the cell through cellular respiration. They convert glucose and oxygen into ATP (adenosine triphosphate), the cell’s main energy source, while releasing carbon dioxide and water as byproducts.
How does volcanic activity influence the formation of new land?
Volcanic eruptions release molten rock (lava) that cools and solidifies, forming new landmasses such as islands and expanding coastlines.
FINAL JEOPARDY: you may bet any number of points that your team has.
A 5 kg object is dropped from a height of 10 meters. Assuming no air resistance and using g=9.8 m/s2 g=9.8m/s2, calculate the object's velocity just before it hits the ground.
v2 = vi2 + 2gh
v2 = 0 + 2 × 9.8m/s2 × 10m
v2 = 196
v = sqrt(196) = 14 m/s