We can solve the problem by requiring the equilibrium of the forces and the equilibrium of torques.
1) Equilibrium of forces:
![T_1 - W_p - W_s + T_2 =0](https://tex.z-dn.net/?f=T_1%20-%20W_p%20-%20W_s%20%2B%20T_2%20%3D0)
where
![W_p = (90kg)(9.81 m/s^2)=883 N](https://tex.z-dn.net/?f=W_p%20%3D%20%2890kg%29%289.81%20m%2Fs%5E2%29%3D883%20N)
is the weight of the person
![W_s = (200kg)(9.81 m/s^2)=1962 N](https://tex.z-dn.net/?f=W_s%20%3D%20%28200kg%29%289.81%20m%2Fs%5E2%29%3D1962%20N)
is the weight of the scaffold
Re-arranging, we can write the equation as
![T_1 = 2845 N-T_2](https://tex.z-dn.net/?f=T_1%20%3D%202845%20N-T_2)
(1)
2) Equilibrium of torques:
![T_1 \cdot 3 m - W_p \cdot 2 m - T_2 \cdot 3m =0](https://tex.z-dn.net/?f=%20T_1%20%5Ccdot%203%20m%20-%20W_p%20%5Ccdot%202%20m%20-%20T_2%20%5Ccdot%203m%20%3D0)
where 3 m and 2 m are the distances of the forces from the center of mass of the scaffold.
Using
![W_p = 883 N](https://tex.z-dn.net/?f=W_p%20%3D%20883%20N)
and replacing T1 with (1), we find
![2845 N \cdot 3 m - T_2 \cdot 3 m - 833 N \cdot 2 m - T_2 \cdot 3 m=0](https://tex.z-dn.net/?f=2845%20N%20%5Ccdot%203%20m%20-%20T_2%20%5Ccdot%203%20m%20-%20833%20N%20%5Ccdot%202%20m%20-%20T_2%20%5Ccdot%203%20m%3D0)
from which we find
![T_2 = 1128 N](https://tex.z-dn.net/?f=T_2%20%3D%201128%20N)
And then, substituting T2 into (1), we find
Well, actually a heat engine using the Carnot cycle whose cold reservoir is maintained at 0 K could in principle be 100% efficient, even if the hot reservoir was merely at the ambient temperature. Since it costs no energy at all to maintain a heat reservoir at the ambient temperature as long as you have a perfect thermal connection to a large thermal capacitor like your swimming pool or a nearby aquifer you’d have built a perpetual motion machine.
Answer:
1 m = 3.28 ft
1 m^2 = 10.76 ft^2
1560 ft^2 / 10.76 ft^2 / m^2 = 145 m^2
Answer:
The variable manipulated or controlled by the experimenter is called the independent variable.
Example:
If the flow velocity at the bottom of a tank is measured by varying the height of water in the tank, we are measuring velocity as a function of water height.
Therefore,
water height = independent variable (controlled)
velocity = dependent variable (measured in response to water height).
Mathematically,
v = f(h)
where v = response variable (dependent)
h = controlled variable (independent).
Answer:
Electrolysis will be slowed.
Explanation:
Cold water is more dense and therefore it can slow down electrolysis process. Efficiency of electrolysis variate with change in temperature of water.The efficiency of electrolysis increases with increase in temperature of the water. If cold water is used then the process will be slowed down.