Answer :
Essay on Sound instruments/sound boxes:
Musical instruments also some times called <em>"sound box"</em>, because the box modifies the sound of an instrument. It also helps in transfer of sound to the surrounding air.
The box is the open chamber in the body of musical instrument
The sound box responds more strongly to vibrations at certain frequencies created by playing instrument. This phenomena is known as resonance.
The resonance impacts on the tone quality.
For example <em>xylophone</em>, which is a musical instrument with wooden bars. These wooden bars are arranged similar to the piano. under each bar of the xylophone there is a resonator tube, which amplifies the sound.
First we will use the concepts of motion kinetics for which the final speed is defined as shown below,

Here,
= Final velocity
= Initial velocity
a = Acceleration
s = Distance
Replacing,


Using the conservation of energy for kinetic energy we have,



Therefore the kinetic energy of the car is 31900J
By Snell's law:
η = sini / sinr. i = 25, η = 1.33
1.33 = sin25° / sinr
sinr = sin25° / 1.33 = 0.4226/1.33 = 0.3177 Use a calculator.
r = sin⁻¹(0.3177)
r ≈ 18.52°
Option A.
God's grace.
Answer:
<em>d. 268 s</em>
Explanation:
<u>Constant Speed Motion</u>
An object is said to travel at constant speed if the ratio of the distance traveled by the time taken is constant.
Expressed in a simple equation, we have:

Where
v = Speed of the object
d = Distance traveled
t = Time taken to travel d.
From the equation above, we can solve for d:
d = v . t
And we can also solve it for t:

Two cars are initially separated by 5 km are approaching each other at relative speeds of 55 km/h and 12 km/h respectively. The total speed at which they are approaching is 55+12 = 67 km/h.
The time it will take for them to meet is:

t = 0.0746 hours
Converting to seconds: 0.0746*3600 = 268.56
The closest answer is d. 268 s
<span> gravitational force varies based on 1/r^2
when you're double the distance =10,000 to 20,000, the force is 4 times smaller so on and so forth.
</span><span>As force is proportional to 1 / {distance squared}, the force will be 1 / 2^2 (i.e. 1/4) of the force at the reference distance (i.e. 1/4 * 600 = 150 lb)
</span>hope this helps