How many times must he see 9 in order to cover all 72 of them ? 72/9 = 8 . He has to see 9 patients 8 times, so he has to work 3 hours 8 times. 3x8=24 hours.
The force in the rod when the temperature is 150 °F is 718.72 pounds-force.
<h3>How to determine the resulting the resulting force due to mechanical and thermal deformation</h3>
Let suppose that rod experiments a <em>quasi-static</em> deformation and that both springs have a <em>linear</em> behavior, that is, force (
), in pounds-force, is directly proportional to deformation. Then, the elongation of the rod due to <em>temperature</em> increase creates a <em>spring</em> deformation additional to that associated with <em>mechanical</em> contact.
Given simmetry considerations, we derive an expression for the <em>spring</em> force (
), in pounds-force, as a sum of mechanical and thermal effects by principle of superposition:
(1)
Where:
- Spring constant, in pounds-force per inch.
- Spring deformation, in inches.
- Rod elongation, in inches.
The <em>rod</em> elongation is described by the following <em>thermal</em> dilatation formula:
(2)
Where:
- Coefficient of linear expansion, in
.
- Initial length of the rod, in inches.
- Initial temperature, in degrees Fahrenheit.
- Final temperature, in degrees Fahrenheit.
If we know
,
,
,
,
and
, then the force in the rod at final temperature is:
![F = \left(1000\,\frac{lb}{in} \right)\cdot \left[0.7\,in + 0.5\cdot\left(6.5\times 10^{-6}\,\frac{1}{^{\circ}F} \right)\cdot (48\,in)\cdot (150\,^{\circ}F-30\,^{\circ}F)\right]](https://tex.z-dn.net/?f=F%20%3D%20%5Cleft%281000%5C%2C%5Cfrac%7Blb%7D%7Bin%7D%20%5Cright%29%5Ccdot%20%5Cleft%5B0.7%5C%2Cin%20%2B%200.5%5Ccdot%5Cleft%286.5%5Ctimes%2010%5E%7B-6%7D%5C%2C%5Cfrac%7B1%7D%7B%5E%7B%5Ccirc%7DF%7D%20%5Cright%29%5Ccdot%20%2848%5C%2Cin%29%5Ccdot%20%28150%5C%2C%5E%7B%5Ccirc%7DF-30%5C%2C%5E%7B%5Ccirc%7DF%29%5Cright%5D)

The force in the rod when the temperature is 150 °F is 718.72 pounds-force. 
To learn more on deformations, we kindly invite to check this verified question: brainly.com/question/13774755
Answer:
a>-1/3
Step-by-step explanation:
-7a-2a<3
-9a<3
-a<3/9
a>-3/9
a>-1/3
You switch the sign because your dividing by a negative.
Answer:
20 movies ; $70
Step-by-step explanation:
Company 1:
Monthly charge = $40 ; additional = 1.5 per movie
Let number of movies = x ; t = cost
Equation 1:
y = 40 + 1.5x
Company 2:
Monthly charge = $30
Additional = $2 per movie
Equation 2:
y = 30 + 2x
1) for equation 1 = equation 2
40 + 1.5x = 30 + 2x
40 - 30 = 2x - 1.5x
10 = 0.5x
x = 10/0.5
x = 20
Hence, 20 movies
B.)
y = 30 + 2x
y = 30 + 2(20)
y = 30 + 40
y = $70