The average density of Earth's crust 10 km beneath the surface is 2.7 gm / cm 3. The speed of longitudinal seismic waves at that depth is 5.4 km / s. The bulk modulus of Earth's crust considering its behaviour as fluid at that depth, is

Question

The average density of Earth's crust 10 km beneath the surface is 2.7 gm / cm 3. The speed of longitudinal seismic waves at that depth is 5.4 km / s. The bulk modulus of Earth's crust considering its behaviour as fluid at that depth, is (A) 7.9 × 1010 Pa (B) 5.6 × 1010 Pa (C) 7.9 × 107 Pa (D) 1.46 × 107 Pa

Tardigrade Admin · Accepted Answer

v=√(B/ρ) ⇒ B =v2 ρ=(5.40 × 103 m / s )2(2.7 × 103) =7.6 × 1010 Pa

Q. The average density of Earth's crust $10 km$ beneath the surface is $2.7 g m / c m^{3}$ . The speed of longitudinal seismic waves at that depth is $5.4 km / s$ . The bulk modulus of Earth's crust considering its behaviour as fluid at that depth, is

$7.9 \times 1 0^{10} P a$

$5.6 \times 1 0^{10} P a$

$7.9 \times 1 0^{7} P a$

$1.46 \times 1 0^{7} P a$

$v = \frac{B}{ρ}$
$\Rightarrow B = v^{2} ρ = (5.40 \times 1 0^{3} m / s)^{2} (2.7 \times 1 0^{3})$
$= 7.6 \times 1 0^{10} P a$

Q. The average density of Earth's crust 10km beneath the surface is 2.7gm/cm3. The speed of longitudinal seismic waves at that depth is 5.4km/s. The bulk modulus of Earth's crust considering its behaviour as fluid at that depth, is

7.9×1010Pa

5.6×1010Pa

7.9×107Pa

1.46×107Pa