Calculate the indicated horsepower of the following engine: 7 cylinders, a stroke length of 0.85 feet, a bore of 4.3 inches, operating at 3240 rpm , and has an indicated mean effective pressure (IMEP) of 1310 psi per cylinder. Round to 1 decimal place.

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To calculate the indicated horsepower (IHP) of the engine, we can use the following formula:

$$
\text{IHP} = \frac{(N \times L \times A \times P_{IMEP})}{33,000}
$$

Where:
- $$ N $$ = number of cylinders
- $$ L $$ = stroke length in feet
- $$ A $$ = area of the bore in square feet
- $$ P_{IMEP} $$ = indicated mean effective pressure in pounds per square foot (psi to psf conversion)
- 33,000 = conversion factor to horsepower

### Step 1: Convert Bore to Feet
The bore is given in inches, so we need to convert it to feet:

$$
\text{Bore} = 4.3 \text{ inches} = \frac{4.3}{12} \text{ feet} \approx 0.3583 \text{ feet}
$$

### Step 2: Calculate the Area of the Bore
The area $$ A $$ of the bore can be calculated using the formula for the area of a circle:

$$
A = \pi \left(\frac{D}{2}\right)^2
$$

Where $$ D $$ is the diameter (bore). Thus,

$$
A = \pi \left(\frac{0.3583}{2}\right)^2 \approx \pi \left(0.17915\right)^2 \approx \pi \times 0.0320 \approx 0.1005 \text{ square feet}
$$

### Step 3: Convert IMEP to Pounds per Square Foot
The IMEP is given in psi, and we need to convert it to pounds per square foot:

$$
P_{IMEP} = 1310 \text{ psi} \times 144 \text{ (square inches per square foot)} = 189840 \text{ psf}
$$

### Step 4: Substitute Values into the IHP Formula
Now we can substitute the values into the IHP formula:

$$
\text{IHP} = \frac{(7 \times 0.85 \times 0.1005 \times 189840)}{33,000}
$$

Calculating the numerator:

$$
7 \times 0.85 \times 0.1005 \times 189840 \approx 7 \times 0.85 \times 0.1005 \times 189840 \approx 7 \times 0.085425 \times 189840 \approx 7 \times 16215.5 \approx 113508.5
$$

Now, divide by 33,000:

$$
\text{IHP} \approx \frac{113508.5}{33,000} \approx 3.44
$$

### Final Result
Rounding to one decimal place, the indicated horsepower of the engine is:

$$
\text{IHP} \approx 3.4 \text{ horsepower}
$$
The indicated horsepower of the engine is approximately 3.4 horsepower.

Calculate the indicated horsepower of the following engine: 7 cylinders, a stroke length of 0.85 feet, a bore of 4.3 inches, operating at 3240 rpm , and has an indicated mean effective pressure (IMEP) of 1310 psi per cylinder. Round to 1 decimal place.

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