If abody droops from height it reach the ground in three second what is hight

44.1m

Explanation:

Let's assume the mass is negligible.

Acceleration due to gravity is 9.8m/s.

Time is 3s.

Use the formula.

Height /distance=ut + 1/2at^2

0 ×3 + 1/2 ×9.8^2

Height = 0+ 1/2×9.8 × 9.8

Height= 44.1m.

In this scinerio, height is the same as distance.

the half-angle "alpha" of the Mach cone = 30⁰

Explanation:

To calculate the  half-angle "alpha" of the Mach cone.

we say ;

Sin∝ = 1 / Ma

given that Ma = 2

now we substitute

Sin∝ = 1 / 2

Sin∝ = 0.5

∝ = Sin⁻¹ 0.5

∝ = 30⁰

Therefore, the half-angle "alpha" of the Mach cone is 30⁰