A gun is a heat engine. In particular, it is an internal combustion piston engin

Question

A gun is a heat engine. In particular, it is an internal combustion piston engine that does not operate in a cycle, but comes apart during its adiabatic expansion process. A certain gun consists of 1.75 kg of iron. It fires one 2.40-g bullet at 330 m/s with an energy efficiency of 1.20%. Assume that the body of the gun absorbs all of the energy exhaust and increases uniformly in temperature for a short time before it loses any energy by heat into the environment. Find its temperature increase. ---------------- 0C

Explanation / Answer

KE of bullet= m v^2 / 2

    = (0.0024 kg) (330 m/s)^2 / 2 = 130.68 J

efficiency = KE / total energy genrated

total energy = 130.68 / 0.012 = 10890 J

energy increasing temp of gun = 10890 - 130.68

          = 10759.32 J

and Q = m Ciron deltaT

10759.32 = 1.75 x 450 x deltaT

deltT = 13.66 deg C

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.