InterviewSolution
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InterviewSolution
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(a)Define critical velocity. (2)Derive the formula of critical velocity |
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Answer» Solution :(a)The satellite is given a specific velocity known as the critical velocity `(V_c)` in a tangential DIRECTION to the orbit. The satellite then starts revolving around the earth. (b) The formula for the velocity `v_c` can be DERIVED as below. If a satellite of mass 'm' is revolving around the earth in an orbit of height 'h' with speed `v_c` then as seen in the chapter on 'Gravitation' , a centripetal force `(mv_c^2)/r` will act on it. Here 'r' is theorbital RADIUS of the satellite from THECENTRE of the earth. This centripetal force is provided by the gravity of the earth. (c ) Therefore , centripetal force = gravitational force between the Earth and satellite. `(mv_c^2)/(R+h)=(GMm)/((R+h)^2)` `V_c^2=(GM)/(R+h)` `v_c=sqrt((GM)/(R+h))` |
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