What is the difference between Direct measurement and Indirect measurement?

Interview Q & A Instrumentation
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Broadly the measurement can be categorized in to two categories

  1. Direct measurement 2. Indirect measurement

Direct measurement

The quantity to be measured is determined directly.

Example – Measure distance by scale

Indirect measurement

The quantity to be measured is not measured directly.But other related parameter is measured and inference is drawn from there.

Example – Measure distance by optical method where we use telescope to calculate distance.