Speed of a watercourse needs to be known, for example, to calculate reliability of a ferry or to define safety of bathing. Speed of a current can differ on different sites.
It is required to you
- Long strong rope, stop watch, floating object of a bright coloring, wooden stakes one meter high, geodetic compasses.
Instruction
1. Find the site of the coast where the watercourse is constant. Establish a wooden stake to the earth, measure from it fifty or hundred meters along the coast, thrust the second stake in this place. Stretch a rope between two pegs. This line has to be parallel to a watercourse.
2. On everyone to a stake fix a direct stick, perpendicular to the line of measurement, at the same time sticks have to be directed to the river. Such sticks are called traverses, they serve for convenient aiming during measurements.
3. Measurements take place as follows: the first person with a floating object leaves upstream from the first peg at which costs the second, observing a current on a traverse. At the same time the third person costs at the second traverse with a stop watch. Necessary muster there begins the third participant, reporting about readiness, then reports about the readiness to the second.
4. The first orders "Start", throwing a floating object into the river. When an object crosses the first traverse, the second participant gives a sound signal on which the third participant of an experiment starts a stop watch. When a floating object crosses the second traverse, the stop watch is switched off.
5. Now, possessing all necessary data, it is easy to calculate the speed of the Po River to a formula v=s/t where s – distance between pegs, t – time which was necessary for a floating subject to overcome this distance, and v – the required speed of a watercourse. Two or three times are the best of all to repeat this experiment, having defined as a result Bol exact average value.