As per given condition Half of kinetic energy is transferred into heat energy and raises the temperature of bullet
21×21mv2=msΔT
Δt=4sV2
=4×4.2×0.3×1000210×210=87.5∘C
JEE Main 2020 — Physics Thermodynamics
A bullet of mass 5gram, travelling with a speed of 210ms−1 strikes a fixed wooden target. One half of its kinetic energy is converted into heat in the wood. The rise of temperature of the bullet if the specific heat of its material is 0.030(gram∘C)−1(1calorie=4.2×107ergs) close to :
Held on 5 Sept 2020 · Verified 6 Jul 2026.
87.5∘C
83.3∘C
119.2∘C
38.4∘C
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