MECHANICS Problem No. 58

Module # MECH_P_058_Douglas_C_Giancoli Statement If you began walking along one of Earth’s lines of longitude and walked north until you had changed latitude by 1 minute of arc (there are 60 minutes per degree), how far would you have walked (in miles)? This distance is called a “nautical mile.” Solution Suppose we walk completely around the Earth along the Meridian then it will constitute a circle whose full 3600 would equal the circumference of Earth. We know that Radius of Earth = X 103 km = 6380 km = 6380000 m 1 mile = 1609 m Circumference of Earth = 2π ( X 103 km) = 40066 km = 40066000m 1 Revolution = 360 degrees = 360 X 60 minutes = 21600 minutes Hence, Circumference per Revolution = 40066000m