The velocity of piston in a reciprocating steam engine is given by (where ω = Angular velocity of crank, r = Radius of crank pin circle, θ = Angle turned by crank from inner dead center, and n = Ratio of length of connecting rod to the radius of crank)

• A. ω²r [cos θ + (cos 2θ/n)]
• B. ωr [cos θ + (cos 2θ/n)]
• C. ω²r [sin θ + (sin 2θ/n)]
• D. ωr [sin θ + (sin 2θ/n)]

Answer: (D)