The escape velocity of a body from the surface of earth is the minimum velocity of projection of the body from the surface, which would take the body just beyound the gravitational field of earth. Once the body crosses the gravitational field of earth, it will never return to earth on its own. The body is said to have esacped. If M is mass of earth and R is radius of earth, then esacpe velocity, V_(e) = sqrt((2GM)/(R )) = sqrt(2gR). The value of V_(e) does not depend upon mass of the body. Read the above passega and answer the following questions : (i) What is the escape velocity from the surface of earth for a body of mass 2 kg and for another body of mass 20 kg? Is the energy required in the two cases same ? (ii) What value of life do you learn from this study ?

The escape velocity of a body from the surface of earth is the minimum

1.	The escape velocity of a body from the surface of earth is the minimum velocity of projection of the body from the surface, which would take the body just beyound the gravitational field of earth. Once the body crosses the gravitational field of earth, it will never return to earth on its own. The body is said to have esacped. If M is mass of earth and R is radius of earth, then esacpe velocity, V_(e) = sqrt((2GM)/(R )) = sqrt(2gR). The value of V_(e) does not depend upon mass of the body. Read the above passega and answer the following questions : (i) What is the escape velocity from the surface of earth for a body of mass 2 kg and for another body of mass 20 kg? Is the energy required in the two cases same ? (ii) What value of life do you learn from this study ?
Answer» Solution :(i) As escape velocity does not depend upon MASS of the body, therefore, value of escape velocity from the surafce of earth for both the bodies is same `(= 11 km//sec)`. No, the energy required in the two CASES shell not the same. This is because, energy required `= (1)/(2) m V_(E)^(2)`, which is directly proportional to `m`. For body of mass `20 kg`, energy required is `10` times the energy required for body of mass `2 kg`. (ii) From this study, we learn that everything has a price. You pay the price and GET the thing. If you are not able to affored the price of something, you cannot get it. This is so true for anything and everthing in life.