Friction occurs when the surfaces and heat of two surfaces grind against each other.
I think these are the answers
Answer:
The frequency of sound wave created by trumpet is 437.5Hz
Explanation:
Given
the speed of sound wave = 350 m
the wavelength of sound wave = 0.8 m
the frequency of sound wave = ?
All the waves have same relationship among wavelength, frequency and speed, which is given by the equation:
v = fλ, where
v is speed of the wave
f is frequency of the wave
λ is wavelength of the wave
therefore frequency of sound wave is given by
f = v/λ
= 350m
/0.8m
= 437.5
= 437.5Hz (since 1
= 1 Hz (Hertz)
Hence the frequency of sound wave created by trumpet is 437.5Hz
The mass of the baked loaf will be less than the original dough. In making dough for bread, we have ingredients that are liquid such as water, melted butter, food flavoring, etc. All of this liquid ingredients mixed on the dough will definitely turn into vapor. This vapor is responsible for releasing of the aroma of the freshly baked bread.
Answer:
1). 
2). Toward us
3). 
4). Toward us
5). 
6). Away from us
7). 
8). Away from us
Explanation:
Spectral lines will be shifted to the blue part of the spectrum if the source of the observed light is moving toward the observer, or to the red part of the spectrum when it is moving away from the observer (that is known as the Doppler effect).
The wavelength at rest is 121.6 nm (
)

Then, for this particular case it is gotten:
Star 1: 
Star 2:
Star 3:
Star 4:
Star 1:
Toward us
Star 2:
Toward us
Star 3:

Away from us
Star 4:

Away from us
Due to that shift the velocity of the star can be determine by means of Doppler velocity.
(1)
Where
is the wavelength shift,
is the wavelength at rest, v is the velocity of the source and c is the speed of light.
(2)
<em>Case for star 1
:</em>
<em></em>
Notice that the negative velocity means that is approaching to the observer.
<em>Case for star 2
:</em>
<em>Case for star 3
:</em>
<em>Case for star 4
:</em>
Hello,
The balloon sticks to a sweater after it has been rubbed against it because once you rub a balloon against the sweater, the balloon steals electrons from the sweater, which leaves the sweater positively charged and the balloon negatively charged.
Mark brainliest if helped!