625=msΔT+mL625=m[125×300+2.5×104]625=m[37500+25000]625=m[62500]m=1001 kgM=10 grams
JEE Main 2025 — Physics Thermodynamics
A gun fires a lead bullet of temperature 300 K into a wooden block. The bullet having melting temperature of 600 K penetrates into the block and melts down. If the total heat required for the process is 625 J , then the mass of the bullet is grams. (Latent heat of fusion of lead =2.5×104JKg−1 and specific heat capacity of lead =125JKg−1 K−1)
Held on 23 Jan 2025 · Verified 6 Jul 2026.
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