This is where we have to admit that gravitational potential energy is
one of those things that depends on the "frame of reference", or
'relative to what?'.
Potential energy = (mass) x (gravity) x (<em>height</em>).
So you have to specify <em><u>height above what</u></em> .
-- With respect to the ground, the ball has zero potential energy.
(If you let go of it, it will gain zero kinetic energy as it falls to
the ground.)
-- With respect to the floor in your basement, the potential energy is
(3) x (9.8) x (3 meters) = 88.2 joules.
(If you let go of it, it will gain 88.2 joules of kinetic energy as it falls
to the floor of your basement.)
-- With respect to the top of that 10-meter hill over there, the potential
energy is
(3) x (9.8) x (-10) = -294 joules
(Its potential energy is negative. After you let go of it, you have to give it
294 joules of energy that it doesn't have now, in order to lift it to the top of
the hill <em>where it will have zero</em> potential energy.)
Answer:
The net emissions rate of sulfur is 1861 lb/hr
Explanation:
Given that:
The power or the power plant = 750 MWe
Since the power plant with a thermal efficiency of 42% (i.e. 0.42) burns 9000 Btu/lb coal, Then the energy released per one lb of the coal can be computed as:
![\mathtt{=( 0.42\times 9000\times 1055.06) J}](https://tex.z-dn.net/?f=%5Cmathtt%7B%3D%28%200.42%5Ctimes%209000%5Ctimes%201055.06%29%20J%7D)
= 3988126.8 J
= 3.99 MJ
Also, The mass of the burned coal per sec can be calculated by dividing the molecular weight of the power plant by the energy released per one lb.
i.e.
The mass of the coal that is burned per sec ![=\dfrac{750}{3.99}](https://tex.z-dn.net/?f=%3D%5Cdfrac%7B750%7D%7B3.99%7D)
The mass of the coal that is burned per sec = 187.97 lb/s
The mass of sulfur burned ![= \dfrac{1.1}{100} \times 187.97 \ lb/s](https://tex.z-dn.net/?f=%3D%20%5Cdfrac%7B1.1%7D%7B100%7D%20%5Ctimes%20187.97%20%5C%20%20lb%2Fs)
= 2.067 lb/s
To hour; we have:
= 7444 lb/hr
However, If a scrubber with 75% removal efficiency is utilized,
Then; the net emissions rate of sulfur is (1 - 0.75) × 7444 lb/hr
= 0.25 × 7444 lb/hr
= 1861 lb/hr
Hence, the net emissions rate of sulfur is 1861 lb/hr
Answer:
scientific law is a statement that summarizes a pattern found in nature.
Thank you for posting your question here at brainly. I hope the answer will help you. Feel free to ask more questions.
Below is the solution:
<span>centripetal accel = 1.5*g
ω²r = 1.5*9.8m/s²
ω² * 8m = 14.7 m/s²
ω = 1.36 rad/s * 1rev/2πrads * 60s/min = 12.9 rpm</span>
Answer:
I = 97.2 10³⁶ kg m²
Explanation:
The moment of inertia of a body the expression of inertia in the rotational movement and is described by the expression
I = ∫ r² dm
In this problem we are told to use the moment of inertia of a uniform sphere, the expression of this moment of inertia is
I = 2/5 M r²
where m is the mass of the earth and r is the radius of the earth.
Let's calculate
I = 2/5 5.97 10²⁴ (6.38 10⁶)²
I = 97.2 10³⁶ kg m²