Iron (Wrought)
Step 1: Young’s modulus ($Y$) measures the stiffness of a material and is defined as: \[ Y = \frac{{Stress}}{{Strain}} \]
Step 2: The values of Young’s modulus for common metals are:
Aluminium: $70 \times 10^9$ Pa
Copper: $110 \times 10^9$ Pa
Brass: $100 \times 10^9$ Pa
Steel: $200 \times 10^9$ Pa
Wrought Iron: $190 \times 10^9$ Pa
Step 3: Since steel has the highest Young’s modulus, it is the stiffest material among the given options.
Step 4: Therefore, the correct answer is (D). \bigskip
Kepler's second law (law of areas) of planetary motion leads to law of conservation of
Kepler's second law (law of areas) of planetary motion leads to law of conservation of