Height of any object can be measured quite precisely the device called the altimeter. It is possible to get on roof of the building and to measure its height tape measure, having lowered it. However if you need to learn building height only once and with low accuracy – for example to make sure that the adjoining house does not cover signal from the satellite which you want to accept on the satellite antenna – there is no reason to buy the expensive device or to get on roof. There are different ways of determination of approximate height of buildings.

## It is required to you

- Tape measure, calculator.

## Instruction

1. Determination of height standard multy-storey to zdaniyposchitayta the number of floors in the building. Increase the received number by 2.9 m and add to work 1.5 and 2 of m. The received value will be approximately equal **to building** height. The specified digits mean: • 2.9 m – average floor height; • 1.5 m – semi-basement height; • 2 m – attic height.

2. Determination of height of the building by means of it teniv sunny day choose two check points on the building: top (on the top of the building) and lower (on the earth at foundation of the building). The lower point has to be located on one vertical from top. Simplest to take top and bottom of corner of the house for check points if it is displayed on shadow. Find the top check point on house shadow. Measure distance from it to the lower check point of the building. Designate this value by letter M.Votknite to the earth in any place lit with the sun pole 1.5-2 m long. Measure length of its shadow. Designate length of pole and length of its shadow as h and m respectively. Determine building height by formula H= (h*M)/m in meters. The formula is based on similarity of triangles, one of which is formed by two check points of the building and shadow the top check point, and another – pole and its shadow.

3. Determination of height of the building by means of cardboard to treugolnikavyrezhta from cardboard or fibreboard right triangle with equal legs (half of square). The leg can be any, for example, 0.5 m. Looking at the top check point of the building through triangle hypotenuse (so that your eye, the hypotenuse of triangle and the top check point were on one line) – recede from the building until the triangle leg (distant from you) does not reach vertical position. Note this place some subject – for example, stone. Measure distance from the found point to the lower check point of the building. Add to it lands. The received value will be equal to building height. For convenience of measurements it is desirable to have the assistant who will control perpendicularity of leg of triangle plumb. It is possible to beat also triangle to pole so that its leg was parallel to pole. It is much simpler to keep vertical position of the pole set against the earth, than to control the provision of triangle. As well as in the previous case this way is based on similarity of triangles – cardboard and formed by connection of three points – your eye, the top and lower check points of the building.