Answer:

Explanation:
P = Acoustic power = 63 µW
r = Distance to the sound source = 210 m
Acoustic power

Threshold intensity = 
Ratio

Ratio of the acoustic intensity produced by the juvenile howler to the reference intensity is 113.68
The relationship between mass m, volume V and density d is:

The silver has density

, and the mass of the piece of silver is

. Therefore we can calculate its volume using the previous formula:
Answer:
n=2.053
Explanation:
We will use Snell's Law defined as:

Where n values are indexes of refraction and
values are the angles in each medium. For vacuum, the index of refraction in n=1. With this we have enough information to state:

Solving for
yields:

Remember to use degrees for trigonometric functions instead of radians!
I attached a free body diagram for a better understanding of this problem.
We start making summation of Moments in A,



Then we make a summation of Forces in Y,



At the end we calculate the angle with the sin.


Answer:
Explanation:
Answer:
Explanation:
Given that,
System of two particle
Ball A has mass
Ma = m
Ball A is moving to the right (positive x axis) with velocity of
Va = 2v •i
Ball B has a mass
Mb = 3m
Ball B is moving to left (negative x axis) with a velocity of
Vb = -v •i
Velocity of centre of mass Vcm?
Velocity of centre of mass can be calculated using
Vcm = 1/M ΣMi•Vi
Where M is sum of mass
M = M1 + M2 + M3 +...
Therefore,
Vcm=[1/(Ma + Mb)] × (Ma•Va +Mb•Vb
Rearranging for better understanding
Vcm = (Ma•Va + Mb•Vb) / ( Ma + Mb)
Vcm = (m•2v + 3m•-v) / (m + 3m)
Vcm = (2mv — 3mv) / 4m
Vcm = —mv / 4m
Vcm = —v / 4
Vcm = —¼V •i