A liquid compressed in cylinder has a volume of $0.04m^3$ at $50 kg/cm²$ and a volume of $0.039m^3$ at $150 kg/cm²$. The bulk modulus of elasticity of liquid is
- A. 400 $kg/cm²$
- B. $40 \times 10^6 kg/cm²$
- C. $40 \times 10^5 kg/cm²$
- D. 4000 $kg/cm²$
Answer: D. 4000 $kg/cm²$
Explanation: $K = -V \frac{\Delta P}{\Delta V} = -0.04 \frac{150-50}{0.039-0.04} = -0.04 \frac{100}{-0.001} = 4000$.