Answer:
A
Explanation:
There is a mechanical advantage in this system....
she only needed 100 N to lift 500 N
1:5 she lifted it 2 meters, so if there WAS NO friction, she would have to pull in 5 x 2 = 10 meters
but there IS friction so she must have pulled in MORE than 10 m
Answer:

Explanation:
Let assume that cooling water works under a pressure of 1 atmosphere. The time required to boil half of the water is determined by the First Law of Thermodynamics:
![\dot Q \cdot \Delta t = m \cdot [c_{p,w}\cdot (T_{2}-T_{1})+h_{fg}]](https://tex.z-dn.net/?f=%5Cdot%20Q%20%5Ccdot%20%5CDelta%20t%20%3D%20m%20%5Ccdot%20%5Bc_%7Bp%2Cw%7D%5Ccdot%20%28T_%7B2%7D-T_%7B1%7D%29%2Bh_%7Bfg%7D%5D)
![\Delta t = \frac{m\cdot [c_{p,w}\cdot (T_{2}-T_{1})+h_{fg}]}{\dot Q}](https://tex.z-dn.net/?f=%5CDelta%20t%20%3D%20%5Cfrac%7Bm%5Ccdot%20%5Bc_%7Bp%2Cw%7D%5Ccdot%20%28T_%7B2%7D-T_%7B1%7D%29%2Bh_%7Bfg%7D%5D%7D%7B%5Cdot%20Q%7D)
![\Delta t = \frac{(2.25\times 10^{5}\,kg)\left[\left(4.186\,\frac{kJ}{kg\cdot ^{\textdegree}C} \right)\cdot (100\,^{\textdegree}C - 10\,^{\textdegree}C)+2256.5\,\frac{kJ}{kg} \right]}{200000\,kW}](https://tex.z-dn.net/?f=%5CDelta%20t%20%3D%20%5Cfrac%7B%282.25%5Ctimes%2010%5E%7B5%7D%5C%2Ckg%29%5Cleft%5B%5Cleft%284.186%5C%2C%5Cfrac%7BkJ%7D%7Bkg%5Ccdot%20%5E%7B%5Ctextdegree%7DC%7D%20%5Cright%29%5Ccdot%20%28100%5C%2C%5E%7B%5Ctextdegree%7DC%20-%2010%5C%2C%5E%7B%5Ctextdegree%7DC%29%2B2256.5%5C%2C%5Cfrac%7BkJ%7D%7Bkg%7D%20%5Cright%5D%7D%7B200000%5C%2CkW%7D)

Answer: 2. Solution A attains a higher temperature.
Explanation: Specific heat simply means, that amount of heat which is when supplied to a unit mass of a substance will raise its temperature by 1°C.
In the given situation we have equal masses of two solutions A & B, out of which A has lower specific heat which means that a unit mass of solution A requires lesser energy to raise its temperature by 1°C than the solution B.
Since, the masses of both the solutions are same and equal heat is supplied to both, the proportional condition will follow.
<em>We have a formula for such condition,</em>
.....................................(1)
where:
= temperature difference
- c= specific heat of the body
<u>Proving mathematically:</u>
<em>According to the given conditions</em>
- we have equal masses of two solutions A & B, i.e.

- equal heat is supplied to both the solutions, i.e.

- specific heat of solution A,

- specific heat of solution B,

&
are the change in temperatures of the respective solutions.
Now, putting the above values


Which proves that solution A attains a higher temperature than solution B.
Answer:
the answer is A Cycles of solar flares and prominences heat and cool the layers below the sun’s surface
Explanation:
i took the quiz
This question is incomplete, the complete question is;
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A constant force F = 6i+8j-6k moves an object along a straight line from point (6, 0, -10) to point (-6, 7, 2).
Find the work done if the distance is measured in meters and the magnitude of the force is measured in newtons.
Answer:
the work done is -88 J
Explanation:
Given the data in the question;
we know that;
Work done = F × S
where constant force F = ( 6i + 8j - 6k )
S = ( -6i + 7j + 2k ) - ( 6i + 0j - 10k )
S = ( (-6i - 6i) + (7j - 0j) + ( 2k - ( -10k) ) )
S = ( -12I + 7j + 12k )
so
Work force = ( 6i + 8j - 6k ) × ( -12I + 7j + 12k )
Work force = ( 6 × -12 ) + ( 8 × 7 ) + ( -6 × 12 )
Work force = -72 + 56 - 72
Work force = -88 J
Therefore, the work done is -88 J