Question

Young’s modulus of steel is 1.9 × 10¹¹ N/m². When expressed in CGS units of dynes/cm², it will be equal to (1N = 10⁵ dyne, 1m² = 10⁴ cm²)

पर्याय

• 1.9 × 10¹⁰

• 1.9 × 10¹¹

• 1.9 × 10¹²

• 1.9 × 10¹³

Answer 1

1.9 × 10¹² 

Explanation:

According to the problem,

Young’s modulus, Y = 1.9 × 10¹¹ N/m²

1N in SI system of units = 10⁵ dyne in C.G.S system.

Hence, Y = 1.9 × 10¹¹ × 10⁵ dyne/m²,

In C.G.S. length is measured in the unit ‘cm’, so we should also convert m into cm.

∴ Y = `1.9 xx 10^11  ((10^5  "dyne")/(10^4  cm^2))`   ......[∵ 1 m = 100 cm]

= 1.9 × 10¹² dyne/cm²