Answer:
The value is 
Explanation:
From the question we are told that
The work input is
The heat delivered is 
The value of A is A = 14
The value of B is B = 72
Generally the efficiency of the heat engine is mathematically represented as

Here
is the total out energy produce by the heat engine and this is mathematically represented as

=> 
=> 
So

=> 
=> 
=> 
The frequency of a wave is the reciprocal of its period.
A period of 0.008 sec means a frequency of
1 / 0.008 sec = 125 per sec . (125 Hz)
GPE= 70.56 J -------------------> GPE= mgh-------------> X= height
70.56 = 6(kg) * 9.8(m/s/s) * X
70.56 = 58.8X
70.56/58.8= 58.8X/58.8
X= 1.2
The height is 1.2 feet or meters (whatever unit you are using in this problem)
Phytophotodermatitis happens when certain plant chemicals cause the skin to become inflamed following exposure to sunlight.
The distance of an object from the mirror's vertex if the image is real and has the same height as the object is 39 cm.
<h3>What is concave mirror?</h3>
A concave mirror has a reflective surface that is curved inward and away from the light source.
Concave mirrors reflect light inward to one focal point and it usually form real and virtual images.
<h3>
Object distance of the concave mirror</h3>
Apply mirrors formula as shown below;
1/f = 1/v + 1/u
where;
- f is the focal length of the mirror
- v is the object distance
- u is the image distance
when image height = object height, magnification = 1
u/v = 1
v = u
Substitute the given parameters and solve for the distance of the object from the mirror's vertex
1/f = 1/v + 1/v
1/f = 2/v
v = 2f
v = 2(19.5 cm)
v = 39 cm
Thus, the distance of an object from the mirror's vertex if the image is real and has the same height as the object is 39 cm.
Learn more about concave mirror here: brainly.com/question/27841226
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