Answer:

Explanation:

The hippopotamus hearing threshold is 100dB

β = 100 dB

The threshold of human hearing is Io = 1 × 10^-12 W/m²

The sound intensity level is given as

β = 10•Log(I / Io)

100 = 10•Log(I / Io)

Divided Both sides by 10

100 / 10 = Log(I / Io)

10 = Log(I / Io)

Take inverse Logarithm ( antilog) of both sides

10^10 = 10^[Log(I / Io)]

10^10 = I / Io

Then,

I = 10^10 × Io

I = 10^10 × 1 × 10^-12

I = 1 × 10^-2 W/m²

I = 0.01 W/m²

The sound intensity is 0.01 W/m²

**Answer:**

a) It reduces the kinetic energy loss of the stunt person.

here we can use energy conservation

like initial kinetic + potential energy is always conserved and it will be same at all points

so we can say

now we can plug in all the given values in it

now divide whole equation by mass "m"

so final speed will be 65.96 m/s

**Answer:**

**Explanation:**

The cross sectional area of the hole can be find using

Δ

Steel coefficient

replacing to find A

Considering that the acceleration is uniform

we apply the equation

with zero initial speed

and we obtain the speed

Thus