Question

Which of the following is the purpose of balance indicator in double beam photometer or colorimeter?

(a) Selects a particular wavelength

(b) Splits the wavelength selected into two equal beams

(c) Detects and indicates the amount of light falling on it

(d) Indicates the difference between the output of two photometers

I got this question in an interview for job.

The query is from Single Beam and Double Beam Instruments topic in division Colorimetry and Spectrometry of Analytical Instrumentation

Answer 1

The correct answer is (d) Indicates the difference between the output of two photometers

To elaborate: It compares the output of the two photometers obtained using two beams. It indicates the output.