Question 1: Define Red Shift and explain its significance in the study of the universe.

Answer: Red Shift is the phenomenon where light from an object moving away from the observer is shifted towards the red end of the spectrum. It indicates that the universe is expanding, as observed in distant galaxies.

Question 2: Describe the mechanism by which Red Shift occurs in light waves emitted by galaxies.

Answer: Red Shift occurs when a galaxy moves away from us, causing the light waves it emits to stretch, increasing their wavelength and shifting the light towards the red part of the spectrum.

Question 3: Which type of spectrum is observed from galaxies experiencing Red Shift?

Answer: Absorption spectrum

Question 4: Fill in the blank: The faster a galaxy is moving away from us, the greater the __________ of its light.

Answer: Red Shift

Question 5: Calculate the velocity of a galaxy whose light shows a wavelength shift from 500 nm to 510 nm. Use the formula: v = (Δλ / λ) * c, where c = 3 x 10^8 m/s.

Answer: v = ((510 nm - 500 nm) / 500 nm) * 3 x 10^8 m/s = (10 nm / 500 nm) * 3 x 10^8 m/s = 0.02 * 3 x 10^8 m/s = 6 x 10^6 m/s

Question 6: Explain why Red Shift provides evidence for the expanding universe.

Answer: Red Shift demonstrates that galaxies are moving away from us, with greater shifts indicating higher velocities. This observed pattern supports the Big Bang theory, suggesting the universe is expanding uniformly in all directions.

Question 7: Identify the variable that changes in the light spectrum when a galaxy is moving away from Earth.

Answer: Wavelength

Question 8: Discuss a practical method astronomers use to measure Red Shift in distant galaxies.

Answer: Astronomers use spectroscopes to analyse the light from distant galaxies. By comparing the observed spectral lines to known lines, they determine the extent of wavelength shift, calculating the galaxy’s velocity and distance.

Question 9: Which of the following best describes the relationship between the distance of a galaxy and its Red Shift?

Answer: Directly proportional

Question 10: In a hypothetical scenario, a galaxy's light shows a wavelength of 650 nm, shifted from 600 nm. What is the approximate velocity of this galaxy? (Use v = (Δλ / λ) * c).

Answer: Δλ = 650 nm - 600 nm = 50 nm; v = (50 nm / 600 nm) * 3 x 10^8 m/s = 0.0833 * 3 x 10^8 m/s ≈ 2.5 x 10^7 m/s

Question 11: Describe a theoretical experiment to demonstrate how Red Shift can be observed in a laboratory setting, including safety precautions.

Answer: A possible experiment involves using a Doppler shift setup with a laser and moving reflective surface or source. The laser beam reflects off a moving object, causing a shift in the wavelength detectable by a spectrometer. Safety precautions include wearing laser safety goggles, ensuring the laser is properly contained, and avoiding direct eye exposure.