Answer:
10
Explanation:
The decibel or decibel, is a unit that relates two values of sound pressure, and electrical power. the base unit is the bel, but given the amplitude but for practicality, a submultiple, the decibel, is used. It is a scalar expression .
Zero belios is the reference value used as a base, hence a bel is equivalent to 10 decibels and means that there is a power increase of 10 times over the reference value.
Answer:

Explanation:
For light passing through a single slit, the position of the nth-minimum from the central bright fringe in the diffraction pattern is given by

where
is the wavelength
D is the distance of the screen from the slit
d is the width of the slit
In this problem, we have
is the wavelength of the red light
D = 14 m is the distance of the screen from the doorway
d = 1.0 m is the width of the doorway
Substituting n=1 into the equation, we find the distance between the central bright fringe and the first-order dark fringe (the first minimum):

66666666666666666666666666666666666666666666666666666666666666666666666666666666666666
<span>Make the surfaces smoother. Rough surfaces produce more friction and smooth surfaces reduce friction
Lubrication is another way to make a surface smoother
Make the object more streamlined
Reduce the forces acting on the surfaces
<span>Reduce the contact between the surfaces.</span></span>