Don't look now, but the question GIVES you the formula to use, and it GIVES you the numbers to plug into the formula.
The formula to use to find the distance covered by the sound is
<em>Speed = (distance) / (time)</em>
They also give you:
speed = 330 m/s
time = 0.40 second
Stuff the numbers into the formula:
330 m/s = (Distance) / (0.40 second)
Multiply each side by (0.40 second), and you get:
(330 m/s) / (0.4 second) = Distance
<em>825 meters = Distance</em>
Answer:
B. Increasing temperature.
Explanation:
Atmospheric pressure increases with increasing temperature because warm air causes the atmospheric pressure to rise.
Basically, when the molecules contained in air experience a collision, they usually exert forces on one other, and when these molecules become heated, they experience a quick and rapid motion leading to an increased rate of collision. Therefore, as more force is being exerted on the air molecules, the atmospheric pressure tends to rise or increase.
Answer:
Explanation:
Moment of inertia of larger disk I₁ = 1/2 MR²
Moment of inertia of smaller disk I₂ = 1/2 m r ²
Initial angular velocity
We shall apply law of conservation of angular momentum .
initial total momentum = final angular momentum
I₁ X ωi = ( I₁ + I₂ )ωf
1/2 MR² x ωi = 1/2 ( m r² + MR² ) ωf
ωf = ωi / ( 1 + m r²/MR² )
Answer:
an absorber of x-ray
Explanation:
To make x-ray detection/vision work, you will need at least two items: a source of x-ray and absorbed or x-ray.
The object you want to see itself doesn't have to be the source, but it has to absorb some of the rays instead. When doing a chest x-ray test, the medical employee will put your chest between absorber and source. The heart can absorb some of the rays so it will appear more white than lungs who made of air and won't absorb the rays.
Answer:
D.
Explanation:
To solve the problem it is necessary to apply the concepts of Destructive and constructive interference. The constructive interference in tin film is given by
Where,
t = thickness
Wavelenght
m= is an integer
n= film/refractive index
We use this equaton because phase change is only present for gasoline air interface, but not at the gasoline-water interface. <em>The minimum t only would be when the value of m=0 then</em>
Therefore the correct answer is D. The minimum thickness of the film to see ab right reflection is 100nm