Question 1: Define dark mass and dark energy and describe their significance in the universe.

Answer: Dark mass (dark matter) is an unseen form of matter that exerts gravitational pull, affecting galaxy motion. Dark energy is a mysterious force causing the accelerated expansion of the universe.

Question 2: Explain why dark energy is considered to be responsible for the accelerating expansion of the universe.

Answer: Dark energy has a repulsive effect that pushes galaxies apart, causing the universe to expand faster over time.

Question 3: What percentage of the total mass-energy of the universe is estimated to be dark energy?

Answer: Approximately 68%

Question 4: Fill in the blank: Dark matter makes up about ____ of the total mass in the universe.

Answer: 27%

Question 5: Describe one method scientists use to detect dark matter.

Answer: Scientists detect dark matter indirectly by observing its gravitational effects on visible matter, such as galaxy rotation curves and gravitational lensing.

Question 1: Calculate the amount of dark energy in a hypothetical universe with a total mass-energy of 1 x 10^52 joules, where dark energy accounts for 68% of the total.

Answer: 6.8 x 10^51 joules

Question 2: If the density of dark energy in the universe is estimated to be 7 x 10^-27 kg/m^3, calculate the total mass of dark energy in a volume of 1 x 10^78 m^3.

Answer: 7 x 10^51 kg

Question 1: Design a simple experiment concept to demonstrate the gravitational effects of dark matter on galaxy rotation. Include variables to control and safety precautions.

Answer: Students could simulate galaxy rotation using a spinning disk with embedded masses to represent visible matter and additional unseen mass to demonstrate gravitational influence. Variables: mass distribution, rotational speed. Safety: ensure no sharp objects, avoid loose clothing near moving parts.

Question 2: Identify the independent and dependent variables in an experiment investigating how dark energy affects the expansion rate of the universe.

Answer: Independent variable: amount of dark energy; Dependent variable: rate of universe expansion.

Question 1: A recent study suggests that dark energy is increasing in density over time. Discuss how this could affect the future expansion of the universe.

Answer: If dark energy density increases, the universe's expansion would accelerate at an even faster rate, potentially leading to a 'Big Freeze' scenario where galaxies drift apart beyond observable distance.

Question 2: Explain how understanding dark energy can impact technological advancements or industry.

Answer: Understanding dark energy can lead to new insights into the universe's structure, potentially inspiring new technologies in energy manipulation, space travel, or materials science based on cosmic principles.