A construction team gives an estimate of three months to repave a large stretch of a very busy road. The government responds tha
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Answer
To understand this concept it is necessary to understand Newton's Second Law
According to Newtons Second law applied force is equal to rate of change of momentum of a body.
Mathematically,
here, is rate of change of momentum with respect to time
It means If two eggs fall from same height,one on softer surface and other on hard surface that time the momentum of both eggs will remain equal at both the surfaces. But, impact time will be different. On hard surface egg will stop almost instantly so impact time will be small and hence the force on egg will be large therefore the egg will breakup.
On the other hand on the soft surface like a cotton, egg will not stop instantly but it will slow down for a few seconds and then stop due to which the time of impact will increase. Therefore the force on egg will be less and it won't break up.
Complete Question
Two containers have a substantial amount of the air evacuated out of them so that the pressure inside is half the pressure at sea level. One container is in Denver at an altitude of about 6,000 ft and the other is in New Orleans (at sea level). The surface area of the container lid is A=0.0155 m. The air pressure in Denver is PD = 79000 Pa. and in New Orleans is PNo = 100250 Pa. Assume the lid is weightless.
Part (a) Write an expression for the force FNo required to remove the container lid in New Orleans.
Part (b) Calculate the force FNo required to lift off the container lid in New Orleans, in newtons.
Part (c) Calculate the force Fp required to lift off the container lid in Denver, in newtons.
Part (d) is more force required to lift the lid in Denver (higher altitude, lower pressure) or New Orleans (lower altitude, higher pressure)?
Answer:
a
The expression is
b
c
d
From the value obtained we can say the that the force required to open the lid is higher at Denver
Explanation:
The altitude of container in Denver is
The surface area of the container lid is
The altitude of container in New Orleans is sea-level
The air pressure in Denver is
The air pressure in new Orleans is
Generally force is mathematically represented as
So we are told the pressure inside is is half the pressure the at sea level so the the pressure acting on the container would
The pressure at sea level is a constant with a value of
So the which is the difference in pressure within and outside the container is
Therefore
Now substituting values
The force to remove the lid in Denver is
So we are told the pressure inside is is half the pressure the at sea level so the the pressure acting on the container would
The pressure at sea level is a constant with a value of
At sea level the air pressure in Denver is mathematically represented as
=>
Let height at sea level is h = 1
The air pressure at height
=>
Equating the both
Substituting value
So
=>
So