Question 1:
Which of the following is a measure of a star's brightness as seen from Earth?
Explanation: The measure of a star's brightness as seen from Earth is referred to as magnitude.
Question 2:
Which stellar classification is the hottest?
Explanation: The stellar classification system uses letters to denote temperature, and O-type stars are the hottest among the listed options.
Question 3:
Which of the following characteristics determines a star's lifespan?
Explanation: A star's lifespan is primarily determined by its mass. Higher-mass stars have shorter lifespans compared to lower-mass stars.
Question 4:
Which type of galaxy is characterized by a prominent central bulge and tightly wound spiral arms?
Explanation: Spiral galaxies are characterized by a prominent central bulge and tightly wound spiral arms.
Question 5:
Which of the following is a type of galaxy that appears distorted or irregular in shape?
Explanation: Irregular galaxies appear distorted or irregular in shape and do not fit into the well-defined categories of spiral or elliptical galaxies.