Consider the following parts of spectra
Which one of the following is the correct sequence in which their wavelengths increase?
The electric charge is stored in a device called
Which one of the following statements correctly defines power?
In vacuum, the speed of light
To obtain the powerful parallel beams of light from a vehicle's headlight, one must use
Two thin convex lenses of focal lengths 4 cm and 8 cm are separated by a distance of 4 cm in air. The combination will have the focal length