Q. 375.0( 1 Vote )

# A particle is fired vertically upward from the earth’s surface and it goes up to a maximum height of 6400 km. Find the initial speed of the particle.

Answer :

Let the speed of the particle be and mass be .

Therefore, initial kinetic energy ,

initial potential energy of the system is

At the maximum height, the kinetic energy is zero. Therefore,

And the potential energy at a height is

From conservation of energy,

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