Answer:

Explanation:
From the question we are told that:
Sound level intensity

Generally the equation for intensity level is mathematically given by

Where
I= Intensity measured






Answer:
Newton’s third law of motion states that every action has an equal and opposite reaction. This indicates that forces always act in pairs. Reaction forces are equal and opposite, but they are not balanced forces because they act on different objects so they don’t cancel each other out.
Answer:

Explanation:
Given that,
Mass of a boy is 78 kg
Mass of a girl is 65 kg
We need to find the force of gravitational attraction between them if they are 2 m away.
The formula for the gravitational force is given by :

So, the force between them is
.
Answer: 18.27°
Explanation:
Given
Index of refraction of blue light, n(b) = 1.64
Wavelength of blue light, λ(b) = 440 nm
Index of refraction of red light, n(r) = 1.595
Wavelength of red light, λ(r) = 670 nm
Angle of incident, θ = 30°
Angle of refraction of red light is
θ(r) = sin^-1 [(n(a)* sin θ) / n(r)], where n(a) = index of refraction of air = 1
So that,
θ(r) = sin^-1 [(1 * sin 30) / 1.595]
θ(r) = sin^-1 (0.5 / 1.595)
θ(r) = sin^-1 0.3135
θ(r) = 18.27°
125 because f=ma so you would use 100=mx0.75