Answer: W = 11340J
Explanation:
Hey there! I will give the following steps, if you have any questions feel free to ask me in the comments below.
So this is the Formula: Power = Work / Time.
<u>Step 1:</u><em><u> Find the Formula</u></em>
P = W / T
<em><u>
</u></em>
<u>Step 2: </u><u><em>Make W the subject of the equation.</em></u>
W = PT
<u>Step 3:</u><u> </u><u><em>Given.</em></u>
P = 270 Watts, T = 42 seconds
<u>Step 4:</u><u><em> Substitute these values into equation 2
.</em></u>
W = 270(42)
<u>Step 5:</u><u> </u><u><em>Simplify.</em></u>
W = 11340J
The amount of work done was 11340.
~I hope I helped you! :)~
Phytophotodermatitis happens when certain plant chemicals cause the skin to become inflamed following exposure to sunlight.
Answer:
The BOD concentration 50 km downstream when the velocity of the river is 15 km/day is 63.5 mg/L
Explanation:
Let the initial concentration of the BOD = C₀
Concentration of BOD at any time or point = C
dC/dt = - KC
∫ dC/C = -k ∫ dt
Integrating the left hand side from C₀ to C and the right hand side from 0 to t
In (C/C₀) = -kt + b (b = constant of integration)
At t = 0, C = C₀
In 1 = 0 + b
b = 0
In (C/C₀) = - kt
(C/C₀) = e⁻ᵏᵗ
C = C₀ e⁻ᵏᵗ
C₀ = 75 mg/L
k = 0.05 /day
C = 75 e⁻⁰•⁰⁵ᵗ
So, we need the BOD concentration 50 km downstream when the velocity of the river is 15 km/day
We calculate how many days it takes the river to reach 50 km downstream
Velocity = (displacement/time)
15 = 50/t
t = 50/15 = 3.3333 days
So, we need the C that corresponds to t = 3.3333 days
C = 75 e⁻⁰•⁰⁵ᵗ
0.05 t = 0.05 × 3.333 = 0.167
C = 75 e⁻⁰•¹⁶⁷
C = 63.5 mg/L
Answer:
Balanced forces do not cause a change in motion. When balanced forces act on an object at rest, the object will not move. If you push against a wall, the wall pushes back with an equal but opposite force. ... Forces that cause a change in the motion of an object are unbalanced forces.
Answer:
When a negative charge is brought near one end of a conductor electrons are repelled. ... When electric voltage is applied, an electric field within the metal triggers the movement of the electrons, making them shift from one end to another end of the conductor. Electrons will move toward the positive side.