Answer:
mass conservation is valid for all closed system where the mass will remain in the system always
Explanation:
Conservation of mass is applicable everywhere in classical physics
Here we can also apply mass conservation as we know that the initially the beaker and its water content is having total mass of 109.44 g
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now when we heated it to higher temperature then its total mass will be lesser than the initial mass this is because some of the water may evaporate from the system.
Here if we repeat the same experiment with closed boundary then we can see that total mass will be conserved
So here mass conservation is valid for all closed system where the mass will remain in the system always
Answer:
Explanation:
a )
Pressure on the bottom
= hdg
= 2.5 x 820 x 9.8
= 20090 N / m²
b )
force = area x pressure
= 20090 x 10 x 6 N
= 1205400 N
c )
Force on 10m x 2.5 m face
center of gravity of the tank will lie at height 2 .5 / 2 = 1.25 m
Pressure = hdg
= 1.25 x 820 x 9.8
= 10045 N/m²
force = pressure x area
= 10045 x 10 x 2.5
= 251125 N .
Answer:
B.) by interfering with sound waves
Explanation:
As we know that the interference of sound waves is of two types
1). constructive interference
2). destructive interference
now we know that constructive interference means the resultant intensity will be more than the intensity of interfering waves as here two waves are in same phase.
In destructive interference the resultant of two waves is given by the minimum resultant of the intensity as here the phase of two waves are opposite to each other.
So we will say that
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here in case of noise cancelling headphones we know that the phase of noise is always made in opposite phase with the sound which is used to cancelled the noise.
This will reduce the noise and we will get a clear sound
Answer:
She will make the mass of the smiley face twice as massive in order to keep the mobile in perfect balance.
Explanation:
mass of an object is directly proportional to the cube of its length. In this case the length is constant, the mass will also be constant for the smiley face, so that the mobile will be kept in perfect balance.
Therefore, If Anya decides to make the star twice as massive, and not change the length of any crossbar or the location of any object, she will make the mass of the smiley face twice as massive in order to keep the mobile in perfect balance.
I don't like the wording of any of the choices on the list.
SONAR generates a short pulse of sound, like a 'peep' or a 'ping',
focused in one direction. If there's a solid object in that direction,
then some of the sound that hits it gets reflected back, toward the
source. The source listens to hear if any of the sound that it sent
out returns to it. If it hears its own 'ping' come back, it measures
the time it took for the sound to go out and come back. That tells
the SONAR equipment that there IS a solid object in that direction,
and also HOW FAR away it is.
RADAR works exactly the same way, except RADAR uses radio waves.