Given:
Water, 2 kilograms
T1 = 20 degrees Celsius, T2 = 100
degrees Celsius.
Required:
Heat produced
Solution:
Q (heat) = nRT = nR(T2 = T1)
Q (heat) = 2 kilograms (4.184 kiloJoules
per kilogram Celsius) (100 degrees Celsius – 20 degrees Celsius)
<u>Q (heat) = 669.42 Joules
</u>This is the amount of heat
produced in boiling 2 kg of water.
We assign the variables: T as tension and x the angle of the string
The <span>centripetal acceleration is expressed as v²/r=4.87²/0.9 and (0.163x4.87²)/0.9 = </span><span>T+0.163gcosx, giving T=(0.163x4.87²)/0.9 – 0.163x9.8cosx.
</span>
<span>(1)At the bottom of the circle x=π and T=(0.163x4.87²)/0.9 – .163*9.8cosπ=5.893N. </span>
<span>(2)Here x=π/2 and T=(0.163x4.87²)/0.9 – 0.163x9.8cosπ/2=4.295N. </span>
<span>(3)Here x=0 and T=(0.163x4.87²)/0.9 – 0.163x9.8cos0=2.698N. </span>
<span>(4)We have T=(0.163v²)/0.9 – 0.163x9.8cosx.
</span><span>This minimum v is obtained when T=0 </span><span>and v verifies (0.163xv²)/0.9 – 0.163x9.8=0, resulting to v=2.970 m/s.</span>
Answer: Reflection by clouds
Explanation:
Only some shortwave radiation from the sun reaches the Earth's surface because solar radiation is being reflected by thick clouds and thin clouds transmit the solar radiation.
About 31 % of solar radiation is reflected by clouds. The tiny water particle scatters 20-90 % of incoming sunlight giving them a bright white appearance.
Answer:
t = 5.56 s
Explanation:
In order to calculate the time interval taken by the mountain biker to come to a stop, we will use third equation of motion and first find the deceleration:
2as = Vf² - Vi²
where,
a = deceleration = ?
s = distance = 15 m
Vf = Final Velocity = 0 m/s
Vi = Initial Velocity = 5.4 m/s
Therefore,
2a(15 m) = (0 m/s²) - (5.4 m/s)²
a = - 0.972 m/s²
Now, we use 1st equation of motion:
Vf = Vi + at
therefore,
0 m/s = 5.4 m/s + (-0.972 m/s²)(t)
t = (5.4 m/s)/(0.972 m/s²)
<u>t = 5.56 s</u>
Answer:
it will take for the sphere to increase in potential by 1500 V, 503.71 s.
Explanation:
The charge on the sphere after t seconds is:
q = (1.0000049 - 1.0000000) t = 0.0000049 t
The voltage on the surface is
V = k * 
= k 0.0000049 t / R
solve for t
t = (R*V) / (0.0000049 k) = (0.12 * 1500) / (0.0000049 * 
) = 503.71 s
