The Earth orbits around the Sun because it has angular momentum. If we stopped the Earth in orbit and then let it fall straight towards the Sun, how long would it take to reach the Sun in seconds?
Details and assumptions
The mass of the sun is 2*10^30 Kg. The mass of the earth is 6*10^24 Kg. The earth is 149,600,000 Km from the Sun. You may treat the Earth and Sun as point masses.