Answer:
d) 
Explanation:
β₁ = sound level of sound at rock concert = 120 dB
β₂ = sound level of sound due to whisper = 21 dB
I₁ = Intensity of sound at rock concert
I₂ = Intensity of sound due to whisper
sound level of sound at rock concert is given as


Eq-1
sound level due to whisper is given as


Eq-2
subtracting Eq-2 from Eq-1



The car's velocity at time <em>t</em> is given by

It comes to a stop when <em>v</em> = 0, which happens when

or after about 13.9 s.
In this time, the car travels a distance <em>x</em> given by

or about 192 m.
In one complete revolution, each tire covers a distance equal to its circumference,

or about 2.14 m.
This means each tire will complete approximately 192/2.14 ≈ 90 revolutions.
Answer:
<em>t = 1.02 s</em>
Explanation:
friction = 0 N (no slipping)
downward force along the inclined plane = F = mgsin(30.8)
F = ma
⇒ a = 9.81 sin(30.8)
a = 5.02 m/s^2
now we have
displacement = s = 2.6 m
acceleration = a = 5.02m/s^2
initial velocity = Vi = 0m/s
time = t = ?
<u>APPLYING THE 2ND EQUATION OF MOTION:</u>
<em> S = (Vi)(t)+0.5at^2</em>
<em>2.6 = 0(t) + 0.5 * 5.02 * t^2</em>
<em>t = 1.02 s</em>
The point of the orbit closest to Earth<span> is called perigee, while the point farthest from </span>Earth<span> is known as apogee</span>