The Universe and Astronomy
100: What is one major difficulty in obtaining information about the universe?
Answer: Vast distances and light travel time make direct observation difficult.
100: Name two main types of optical telescopes.
Answer: Refracting (uses lenses) and reflecting (uses mirrors).
100: What is the first stage in the lifecycle of a star?
Answer: Nebula (a cloud of gas and dust).
100: What are the SI units for distance and time?
Answer: Distance is measured in metres (m) and time in seconds (s).
100: What is a force?
Answer: A push or pull that may change the motion of an object.
200: What is a galaxy?
Answer: An immense group of stars, gas, dust, and dark matter bound by gravity.
200: What type of telescope detects radio waves from space?
Answer: A radio telescope.
200: What happens in the main sequence stage of a star’s life?
Answer: Nuclear fusion starts, and the star shines steadily for millions or billions of years.
200: Define velocity.
Answer: Speed in a particular direction.
200: State Newton’s First Law of Motion.
Answer: An object will remain at rest or in uniform motion unless acted upon by a force.
300: Name the telescope known for capturing pictures from space and observing distant stars.
Answer: The Hubble Space Telescope.
300: Why is laser light ideal for measuring vast distances in space?
Answer: Because it spreads very little and keeps its energy concentrated.
300: What is a supernova?
Answer: A massive explosion when a large star reaches the end of its life.
300: What formula is used to calculate speed?
Answer: Speed = Distance ÷ Time.
300: Write Newton’s Second Law of Motion formula.
Answer: Force = Mass × Acceleration (F = m × a).
400: How wide is the Milky Way galaxy approximately?
Answer: About 100,000 light years wide.
400: Name two current space observation instruments besides the Hubble Telescope.
Answer: Voyager probe, Kepler telescope, James Webb Telescope (any two).
400: What force causes objects with mass to attract each other?
Answer: Gravity.
400: Name an experiment to measure average speed of a person walking and running.
Answer: Measure the time taken to walk/run a known distance and calculate speed using speed = distance/time.
400: Describe an example of Newton’s Third Law in everyday life.
Answer: When you push a wall, the wall pushes back with equal and opposite force.
500: Describe the Big Bang theory
Answer: The Big Bang theory states the universe began with an explosive expansion from a very hot, dense state. Since then it has been cooling and expanding as it ages
500: What unit is used to measure distances between stars?
Answer: Light years.
500: What can a large star become after a supernova explosion?
Answer: A neutron star or a black hole.
500: What does a ticker timer experiment show?
Answer: It shows constant motion and accelerated motion by marking time intervals on moving tape.
500: What features in cars help protect passengers during crashes, and name one principle behind them?
Answer: Seatbelts, crumple zones, airbags, ABS brakes; they use forces to reduce impact and protect passengers.