Answer:
Explanation:
Since work done is in the form of potential energy, we will use the formula of potential energy here.
We know that,
<h3>P.E. = mgh </h3>
Where,
m = mass = 20 kg
g = acceleration due to gravity = 10 m/s²
h = vertical height = 20 m
So,
<h3>Work done = mgh</h3>
Work done = (20)(10)(20)
Work done = 4000 joules
Work done = 4 kJ
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Answer:
a) <em>8.33 x 10^-6 Pa</em>
b) <em>8.23 x 10^-11 atm</em>
c) <em>1.67 x 10^-5 Pa</em>
d) <em>1.65 x 10^-10 atm</em>
<em></em>
Explanation:
Intensity of the light 
= 2500 W/m^2
speed of light 
<u> </u>= 3 x 10^8 m/s
a) we know that the pressure for for a totally absorbing surface is given as
= 
= 2500/(3 x 10^8) = <em>8.33 x 10^-6 Pa</em>
b) 1 atm = 101325 Pa
= (8.33 x 10^-6)/101325 = <em>8.23 x 10^-11 atm</em>
c) for a totally reflecting surface
= 
= twice the value for totally absorbing
= 2 x 8.33 x 10^-6 = <em>1.67 x 10^-5 Pa</em>
d) 1 atm = 101325 Pa
= 2 x 8.23 x 10^-11 = <em>1.65 x 10^-10 atm</em>
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Below is the solution:
W done by Normal = 0. (make the incline flat, Normal force goes directly up: no work done)
<span>W done by gravity = w*displacement = (11kg*9.8) * 7.5sin(35) = -463J </span>
<span>W done by friction is the opposite of the work done by weight because the object is not moving. Therefore W done by friction = 463J</span>
Calculating Average Atomic Mass<span>. The </span>average atomic mass of an element<span> is the sum of the </span>masses<span> of its isotopes, each multiplied by its natural abundance (the decimal associated with percent of </span>atoms<span> of that </span>element<span> that are of a given isotope).</span>
