Sometimes friction between two objects are so much that they can't even move. So lubricants are applied between them to reduse the friction. lubricants are usually liquid because they can get filled easily between the ups and downs in a rough surface and reduce the friction. remember lubricants only reduce the friction they don't vanish it, there is still some roughness and adhesion between them. ... morehope it helped. thanks
कबीर के दोहे में घास का विशेष अर्थ है क्योंकि इसमें उन्होंने पैरों के नीचे रौंदी जाने वाली घास के बारे में कहा है कि हमें कभी उसे निर्बल या कमजोर नहीं समझना चाहिए क्योंकि उसका छोटा-सा तिनका भी यदि आँख में पड जाए तो कष्टकर होता है। इस घास का वास्तविक संदेश यह है कि हमें समाज में रहने वाले छोटे से छोटे व्यक्ति काे भी कभी कमजोर नहीं समझना चाहिए, क्योंकि यदि वह शक्ति प्राप्त कर ले तो हमें गहरा आघात पहुंचा सकता है।
A is the correct option.A combustion reaction is a reaction in which a substance reacts with oxygen gas, releasing energy in the form of light and heat. Combustion reactions must involve O2 as one reactant. The products of combustion are carbon dioxide and water.
B is the correct option. It si false,actually the Kaleidoscope is based on the principle of multiple reflection. according to this the light ray get reflected by these multiple mirror. when a light ray falls on one mirror , then it get reflected to the another one.
A is the correct option.A beam of light striking the reflecting surface is called incident ray. An incident ray is a ray of light that strikes a surface. The angle between this ray and the perpendicular or normal to the surface is the angle of incidence. The reflected ray corresponding to a given incident ray, is the ray that represents the light reflected by the surface.