42) Newton’s law of gravity is F = G m1 m2 / d2. Can this be… 42) Newton’s law of gravity is F = G m1 m2 / d2. Can this be used to find the force of gravity between the Sun and a planet? If so, what is d? Read Details
4) Newton’s second law of motion states that 4) Newton’s second law of motion states that Read Details
30) Which of the following statements does not use the term… 30) Which of the following statements does not use the term light-year in an appropriate way? Read Details
14) What is the primary reason for making reflecting telesco… 14) What is the primary reason for making reflecting telescopes larger? Read Details
13) New technologies will soon allow astronomers to use X-ra… 13) New technologies will soon allow astronomers to use X-ray telescopes on Earth’s surface. Read Details
31) What do we mean by the observable Universe? 31) What do we mean by the observable Universe? Read Details
38) During the year, the Sun appears in front of different g… 38) During the year, the Sun appears in front of different groups of stars. What are these called? Read Details
16) A star near the north celestial pole, observed from the… 16) A star near the north celestial pole, observed from the northern hemisphere Read Details
15) How did Eratosthenes estimate the size of Earth around 2… 15) How did Eratosthenes estimate the size of Earth around 240 B.C.? Read Details
2) How do electrons inside an atom change energy? 2) How do electrons inside an atom change energy? Read Details