Why is danger red

When a ray of light enters a glass slab, then Ray Optics and Optical Instruments. What is the power of the resultant combination? What accounts for the flow of charge carriers in forward and reverse biasing of silicon p - n diode?

The number of electrons passing through the filament per second will be Current Electricity. Given a current carrying wire of non uniform cross section. Which of the following is constant throughout the length of the wire? Questions from Ray Optics and Optical Instruments. What distance would the microscope have to be moved to focus on the needle again?

The separation between two lenses and magnification respectively are. Then the refractive index of the material of the lens is. The final image in an astronomical telescope with respect to object is. On the back face of slab is a reflecting plane mirror. An observer sees the image of object in mirror as shown in figure.

Distance of image from front face as seen by observer will be. The eyepiece forms a real image of this line. The length of the telescope when the image is formed at the least distance of distinct vision is. Related Stories. Comment 0. Post Comment. Disclaimer: Comments will be moderated by Jagranjosh editorial team.

Comments that are abusive, personal, incendiary or irrelevant will not be published. Please use a genuine email ID and provide your name, to avoid rejection. Since the wavelength of red light is the longest in the visible light, the light of red colour is scattered the least by the air molecules of the atmosphere and therefore the light of red colour can penetrate to a longer distance.

Thus red light can be seen from the farthest distance as compared to other colours of same intensity. Hence it is used for danger signal so that the signal may be visible from the far distance.

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