Answer:
The intensity level in the room is 63 dB
Explanation:
To calculate the intensity of sound in the room, we use the equation of definition of decibels
β = 10 log (I / Io) (1)
With “I” the sound intensity and “Io” the threshold intensity 1.0 10⁻⁻¹² W/m²
To calculate the intensity we will use the initial data and remember the power of the emitted sound is constant, in addition that the sound propagates in three-dimensional form or on a spherical surface
I = P/A ⇒ P = I A
The area of a sphere is 4 π r², where I can calculate of 1
β/10 = log (I/Io)
I / Io = 
I = Io 
I = 1 10⁻¹² 10⁽¹⁰⁰/¹⁰⁾ = 1 10⁻¹² 10¹⁰
I = 1.0 10⁻² W
With this we can calculate the intensity for a distance of 20 m
I = 1.0 10⁻² / ( 4π 20²)
I = 2.0 10⁻⁶ W/m²
We have already found the intensity at the point of interest, so we can calculate the intensity in decibels at this point with equation 1
β = 10 log(2.0 10⁻⁶ / 1.0 10⁻¹²)
β = 10 log ( 2 10⁶) = 10 6.3
β = 63 dB
The intensity level in the room is 63 dB
Answer:
1.196 μm
Explanation:
D = Screen distance = 3 m
= Wavelength = 598 m
y = Distance of first-order bright fringe from the center of the central bright fringe = 4.84 mm
d = Slit distance


For first dark fringe

Wavelength of first-order dark fringe observed at this same point on the screen is 1.196 μm
Answer:
gravitational potential energy.
Explanation:
Gravitational potential energy (GPE) can be defined as an energy possessed by an object or body due to its position above the earth surface.
Mathematically, gravitational potential energy is given by the formula;

Where,
G.P.E represents gravitational potential energy measured in Joules.
m represents the mass of an object.
g represents acceleration due to gravity measured in meters per seconds square.
h represents the height measured in meters.
This ultimately implies that, anytime there is height, the object must have gravitational potential energy.
Hence, an object possesses gravitational potential energy due to its height (position) and the earth's gravitational force.
The football and air resistance between contact
V (speed) = F (frequency) x Wavelength
If we rearrange the formula, making frequency the subject;
F (frequency) = Speed ÷ Wavelength
F = 300,000 m\s x 4.5 e -10m
F = 0.08810409956 Hz