Distance measured by instruments using radio or light waves, geodimeters, techeometry are comes under which measurement method? 

Explanation:

Direct Distance measurement Method:

• The direct distance measurement method is defined as method distances that are actually measured on the surface of the earth using chains, tapes, perambulators, etc.

Indirect Distance measurement Method:

The indirect distance measurement method is defined as the method distances are measured indirectly, not in the field. With the help of the following methods:

1. Optical Method:

• In this method, the principle of optics is used for distance observations

2. Electronic Method: 

• In this method, distances are measured by the propagation, reflection, and subsequent reception of either radio or light waves.

Tacheometry:

• Tacheometry is defined as an optical distance measurement method. The other names given to Tacheometry are Tachymetry of Telemetry.
• Tachiometry is a branch of angular surveying in which horizontal and vertical distances are obtained by optical means as opposed to the usual process of chain and tape.
• This is done with the help of two special types of instruments Transit-Theodolite and Stadia Rod.

Geodimeter:

• Geodimeter is an optical-electronic distance measurement instrument.
• It is based on the propagation of modulated light waves.
• It measures distance rapidly over long distances.