Created for PHCA by Dick Heckathorn 28 October 2K + 5 How Big Is The Sun? page 88 Created for PHCA by Dick Heckathorn 28 October 2K + 5

three of the numbers (distances) When solving for the 4th number, The size of the sun can be determined by a simple ratio. In this ratio three of the numbers (distances) will be measured. When solving for the 4th number, it will represent the diameter of the sun.

Fasten the apparatus to a meter stick. One end will have a small hole punched in it. The other end contains graph paper on it.

sunlight passes through the hole and strikes the graph paper Orient the meter stick towards the sun so that the sunlight passes through the hole and strikes the graph paper at the other end.

Since the hole and the card are 1 meter apart, identify this as ‘a’ Measure the diameter of the sun’s image on the graph paper. Call this measurement ‘d’. Since the hole and the card are 1 meter apart, identify this as ‘a’ The average distance between the earth and sun is 150,000,000 kilometers. Identify this value as ‘L’ Our forth variable ‘D’ represents the diameter of the sun which we wish to find.

S U N d D a L d = ____________ a = 1 meter L = 150,000,000 km or 1.5 x 1010 meters D = the diameter of the sun. S U N D d a L

S U N d D a L d = ____________ a = 1 meter L = 150,000,000 km Hole in apparatus D d a L d = ____________ a = 1 meter L = 150,000,000 km D = the diameter of sun

d = ____________ a = 1 meter L = 150,000,000 km D = the diameter of sun

The actual diameter of the sun is 1,392,000,000 meters How big is the sun compared to the earth is the diameter of the earth is 130,000,000 m? 107

That’s all folks!