An iron rocket fragment initially at `-100^@C` enters the earth's atmosphere almost horizontally and
Channel: Doubtnut
Date: 2020-07-26

An iron rocket fragment initially at `-100^@C` enters the earth's atmosphere almost horizontally and quickly fuses completely in atmospheric friction. Specific heat of iron is `0.11 kcal//kg^@C`. Its melting point is `1535^@C` and the latent heat of fusion is `3 kcals//kg`. The minimum velocity with which the fragmento must have entered the atmosphere is