Gravity affects any body which is at the Earth's surface (or any other celestial body). For calculation it is enough to learn body weight. For best accuracy it is necessary to measure acceleration of gravity in each concrete point or to use the law of universal gravitation.
It is required to you
- Scales, stop watch, dynamometer
Instruction
1. Suspend a body on a dynamometer or establish on its platform. At the same time the body and the device have to be in rest or move evenly and rectilinearly. Instrument readings will be equal to the body weight which is equal in such conditions to the gravity operating on it.
2. For calculation of average value of gravity measure by means of scales body weight in kilograms. Then increase this weight by number 9.81 (average value of acceleration of gravity on the Earth's surface, g) F=m•g. Receive result in newtons.
3. If at measurement of gravity the special accuracy is necessary, measure acceleration of gravity in this point. For this purpose take the mathematical pendulum (a small body on rather long inextensible thread) and measure its length. Force it to hesitate with a small amplitude, and count the number of fluctuations during 60 pages. After that divide time into the number of fluctuations, time of one fluctuation or the period will be result.
4. Calculate acceleration of gravity, having multiplied number 2, 3.1416 in a square and pendulum length, and divide result into g=4 period square • (3.1416) ²\• L/T². Increase body weight by the received number and receive the gravity which affects it.
5. Generally you find gravity from the law of universal gravitation where one of the interacting bodies is the mother Earth. For this purpose measure a lot of business on which gravity is measured and also its height over the Earth's surface. Calculate gravity. For this purpose increase a gravitational constant by the mass of Earth and body weight, and divide result into the sum of radius of Earth and height of a body over its surface in a square of F=G·M·m/(R+h)².