Here are the solutions to your questions:
Question 3
1. Derive the formula which shows the interrelationship between pressure and temperature.
Let P be the pressure in psi and T be the temperature in degrees.
The problem states that for every 2 psi drop in pressure, the temperature rises by 3 degrees. This indicates a linear relationship between temperature and pressure, T=mP+c.
Step 1: Determine the slope (m).
The change in pressure is ΔP=−2 psi (pressure drops).
The change in temperature is ΔT=+3 degrees (temperature rises).
The slope m is given by:
m=ΔPΔT=−23=−23
Step 2: Use the given point to find the y-intercept (c).
We are given that when the pressure is P=2 psi, the temperature is T=−12 degrees.
Substitute these values and the slope into the linear equation T=mP+c:
−12=(−23)(2)+c
−12=−3+c
Step 3: Solve for c.
c=−12+3
c=−9
Step 4: Write the final formula.
Substitute the slope m=−23 and the y-intercept c=−9 into T=mP+c:
T=−23P−9
The formula showing the interrelationship between pressure and temperature is:
T=−23P−9
2. Draw the graph of the above function, show the intersection points on the graph with the axes precisely.
The function is T=−23P−9.
To draw the graph, we find the intercepts with the axes.
Step 1: Find the T-intercept (where P=0).
Substitute P=0 into the equation:
T=−23(0)−9
T=−9
The T-intercept is (0,−9).
Step 2: Find the P-intercept (where T=0).
Substitute T=0 into the equation:
0=−23P−9
Add 9 to both sides:
9=−23P
Multiply by −32 to solve for P:
P=9×(−32)
P=−3×2
P=−6
The P-intercept is (−6,0).
Step 3: Draw the graph.
Plot the two intercepts (0,−9) and (−6,0) and draw a straight line through them.
The horizontal axis represents Pressure (P in psi) and the vertical axis represents Temperature (T in degrees).
^ T (degrees)
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