Answer:
the claim is not valid or reasonable.
Explanation:
In order to test the claim we will find the maximum and actual efficiencies. maximum efficiency of a heat engine can be found as:
η(max) = 1 - T₁/T₂
where,
η(max) = maximum efficiency = ?
T₁ = Sink Temperature = 300 K
T₂ = Source Temperature = 400 K
Therefore,
η(max) = 1 - 300 K/400 K
η(max) = 0.25 = 25%
Now, we calculate the actual frequency of the engine:
η = W/Q
where,
W = Net Work = 250 KJ
Q = Heat Received = 750 KJ
Therefore,
η = 250 KJ/750 KJ
η = 0.333 = 33.3 %
η > η(max)
The actual efficiency of a heat engine can never be greater than its Carnot efficiency or the maximum efficiency.
<u>Therefore, the claim is not valid or reasonable.</u>
Answer:
The required radial distance from the center of the toroid is -
<u>r = 4.34 cm</u>
Explanation:
We know that magnetic field inside a solenoid is given by -
B = μni
where 'μ' is the magnetic permeability , 'n' is the number of turns per unit length , 'i' is the current passing through solenoid.
given n = 550 turns/meter
We know that magnetic field inside a toroid is -
B = μ××i [Current is same in both the devices] , where 'N' is the total number of turns in the toroid and 'r' is the radial distance from the center of the toroid.
Given N = 150.
Equating the two magnetic fields , we get -
μni = μ××i
∴
Substituting the values we get -
r = 0.0434 m = 4.34 cm
To solve this problem it is necessary to apply the concepts related to intensity as a function of power and area.
Intensity is defined to be the power per unit area carried by a wave. Power is the rate at which energy is transferred by the wave. In equation form, intensity I is
The area of a sphere is given by
So replacing we have to
Since the question tells us to find the proportion when
So considering the two intensities we have to
The ratio between the two intensities would be
The power does not change therefore it remains constant, which allows summarizing the expression to
Re-arrange to find
Therefore the intensity at five times this distance from the source is
Perhaps his refrigerator looks like it's made of stainless steel, but is actually not.
Yeah, bright planet Jupiter and Saturn will align perfectly on December 21 to create what is commonly called the Christmas store or the star of Bethlehem period of corn to NASA, Jupiter and Saturn align well with one another every 20 years or so but not nearly as close together as they will be in 2020.