Question 1: Briefly explain what the Big Bang Theory describes about the origin of the universe.

Answer: The Big Bang Theory describes how the universe began from an extremely hot and dense point approximately 13.8 billion years ago and has been expanding ever since.

Question 2: Define cosmic microwave background radiation and its significance in supporting the Big Bang Theory.

Answer: Cosmic microwave background radiation is the faint thermal radiation filling the universe, detected in all directions, providing evidence of the universe's hot, dense origin as predicted by the Big Bang Theory.

Question 3: Explain why the universe is considered to be expanding according to the Big Bang Theory.

Answer: The universe is expanding because galaxies are moving away from each other, as shown by redshift observations, indicating space itself is stretching since the Big Bang.

Question 4: What is the approximate age of the universe according to current scientific estimates?

Answer: Approximately 13.8 billion years.

Question 5: Multiple Choice: Which of the following observations most strongly supports the Big Bang Theory?

Answer: The existence of cosmic microwave background radiation

Question 6: Fill in the blank: The redshift of galaxies is evidence that the universe is __________.

Answer: expanding

Question 7: Calculate the approximate rate of expansion of the universe if a galaxy 1 billion light-years away is observed to be receding at a speed of 70,000 km/s. Use Hubble's Law: v = H₀ × d, where v is velocity, d is distance, and H₀ is Hubble's constant (approx. 70 km/s/Mpc). (Note: 1 Mpc ≈ 3.086 × 10^19 km).

Answer: H₀ ≈ 70 km/s/Mpc (by definition). Given distance d = 1 billion light-years ≈ 306.6 Mpc. Velocity v = 70,000 km/s. Hubble's Law: H₀ = v / d = 70,000 km/s / 306.6 Mpc ≈ 228 km/s/Mpc. (Note: This is a simplified calculation; actual Hubble's constant is about 70 km/s/Mpc, but this illustrates the method.)

Question 8: Describe a basic experimental method to estimate the age of the universe using observations of distant galaxies.

Answer: Scientists measure the redshift of distant galaxies to determine their recession speeds using Hubble's Law. By calculating the rate of expansion (Hubble's constant), they estimate the time since the galaxies began moving apart, giving an approximate age of the universe. This involves observing galaxy spectra, analysing redshifts, and applying cosmological models.

Question 9: Explain how the Big Bang Theory influences current technologies or industries, providing a specific example.

Answer: The Big Bang Theory has led to the development of technologies like radio telescopes and satellite imaging, which are used in communication, weather forecasting, and space exploration.