Answer:
I₂ = 0.04 W / m²
Explanation:
Sound intensity is the power emitted between the unit area
I = W / A
W = I A
sound is a wave that travels in space whereby its energy is distributed on the surface of a sphere
A = 4π r²
we substitute
W = I (4π r²)
the emission power is constant, so the intensity at two different points is
W = I₁ 4π r₁² = I₂ 4π r₂²
so the equation is
I₁ r₁² = I₂ r₂²
In this case the units are not shown in the exercise, suppose that all units are in the SI system
I₂ = 
let's calculate
I₂ = 4 
I₂ = 0.04 W / m²
Gravitational potential energy added =
(mass) x (gravity) x (distance lifted)
= (852 kg) x (9.8 m/s²) x (3.5 m)
= (852 x 9.8 x 3.5) kg-m²/s²
= 29,223.6 joules
Answer:
Air does, in fact, have weight, and here's a simple way you can prove it. You'll need two identical balloons, a string, and a dowel. Attach the uninflated balloons to either end of the dowel. Attach the string to the center of the dowel and then hang it from something.
Explanation:
Answer:
The mouse runs faster to have the same kinetic energy as the elephant.
Explanation:
Note from the equation given, mass (m) is directly proportional to KE. This means an elephant with more mass will have more KE, therefore, for the mouse to compensate, it has to run faster because its KE is smaller because of its small mass. If both run at the same speed, the elephant would have thousands of times more kinetic energy than the mouse. So the mouse has to run faster so that its speed compansates for its smaller weight.
