The instruments which provide electromagnetic radiation of specified wave length or a band of wave lengths to illuminate the earth surface are called:

Which one of the following factors does not affect the scale of the air photographs?

A. Focal length

B. Flying height

C. Ground elevation

D. None of these

The optical property of a water body depends on:

A. Absorption by the dissolved material

B. Absorption by the suspended particulate matter

C. Scattering by the suspended particulate matter

D. All of these

The infrared portion of EMR lies between

A. 0.4 - 0.7 μm

B. 0.5 mm to 1 μm

C. 0.7 - 1.3 μm

D. 0.7 to 14 μm

The phase difference of the waves 1 and 2 at A in the given figure is:

A. $$\frac{\pi }{4}$$

B. $$\frac{\pi }{2}$$

C. $$\pi $$

D. $$\frac{{3\pi }}{2}$$