21 feet per second equals 640.08 centimeters per second |
21 feet per second equals 21 feet per second |
21 feet per second equals 23.04269566 kilometers per hour |
21 feet per second equals 12.44226732 knots |
21 feet per second equals 6.4008 meters per second |
21 feet per second equals 14.31818182 miles per hour |