Did I Get This With an altitude of approximately 5000 ft above sea level, the typical barometric pressure in Denver, Colorado, is 615 mm Hg. Why is this pressure significantly less than typical barometric pressure at sea level (760 mmHg)? Submit and Compare Convert the typical atmospheric pressure in Denver (615 mmHg) to units of atm 0.809 atm. Correct. 1 atm 1615 mulig 0.809 atm 760 mmlig You are likely familiar with measuring your tire pressure in units of psl (pounds per square inch). Your tire pressure gauge reads 32.5 psi. What is this pressure in kPa? (14.7 psi -1 atm) kPa
The correct answer and explanation is :
To convert tire pressure from psi to kPa, we need to follow a two-step unit conversion:
🔢 Given:
- Tire pressure = 32.5 psi
- 1 atm = 14.7 psi
- 1 atm = 101.325 kPa
✅ Step 1: Convert psi to atm
$$
\frac{32.5 \, \text{psi}}{14.7 \, \text{psi/atm}} = 2.2109 \, \text{atm}
$$
✅ Step 2: Convert atm to kPa
$$
2.2109 \, \text{atm} \times 101.325 \, \text{kPa/atm} = 224.02 \, \text{kPa}
$$
✅ Final Answer:
$$
\boxed{224.02 \, \text{kPa}}
$$
📘 Explanation (300+ words):
Pressure is a physical quantity defined as the force applied per unit area. It is measured in various units, including mmHg (millimeters of mercury), atm (atmospheres), psi (pounds per square inch), and kPa (kilopascals). Each unit has its own typical use. For instance, mmHg and atm are common in atmospheric science and chemistry, psi is used in mechanical systems like tire gauges, and kPa is part of the SI system used in physics and engineering.
To convert tire pressure from psi to kPa, we need to understand how these units relate to the standard atmospheric pressure. At sea level, the standard atmospheric pressure is:
- 1 atm = 14.7 psi
- 1 atm = 101.325 kPa
Therefore, 1 psi is equivalent to:
$$
1 \, \text{psi} = \frac{101.325 \, \text{kPa}}{14.7 \, \text{psi}} \approx 6.8947 \, \text{kPa}
$$
So we can directly use this factor to convert 32.5 psi to kPa:
$$
32.5 \, \text{psi} \times 6.8947 \, \text{kPa/psi} \approx 224.1 \, \text{kPa}
$$
This confirms the result using the two-step method earlier.
Understanding unit conversions is crucial in science and everyday applications. For example, if a car manufacturer specifies tire pressure in kPa and your gauge only shows psi, you’ll need to convert values correctly to maintain safe tire conditions. Under- or over-inflated tires can result in poor fuel economy, reduced handling performance, or even accidents.
By knowing the relationship between these pressure units, you can switch between systems confidently and ensure accurate readings no matter what unit your device uses.