A 0.0030-kg lead bullet is traveling at a speed of 300 m/s when it embeds in a block of ice at 0$\degree$C. If all the heat generated goes into melting ice, what quantity of ice is melted? (L_f = 80 kcal/kg, the specific heat of lead = 0.03 kcal/kg·$\degree$C, and 1 kcal = 4186 J) A) 1.47 *10 ^- ²kg B) 4.0 *10 ^- ⁴ kg C) 3.2 *10^-³ kg D) 2.6 *10^-⁴ kg

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Quizplus · Accepted Answer

The kinetic energy of the bullet is converted into heat, which melts the ice. The kinetic energy is (1/2)mv^2 = (1/2)(0.0030 kg)(300 m/s)^2 = 135 J. Converting this to kcal: 135 J / 4186 J/kcal = 0.0323 kcal. The amount of ice melted is given by the heat divided by the latent heat of fusion: 0.0323 kcal / 80 kcal/kg = 4.0 x 10^-4 kg.

A 00030-Kg Lead Bullet Is Traveling at a Speed of 300