If a force of 100 kPa is applied over a plunger with a diameter of 4 cm, what is the pressure?

If a force of 100 kPa is applied over a plunger with a diameter of 4 cm, what is the pressure?

• A. 5.0 N/m²
• B. 3.9 N/m²
• C. 7.9 N/m²
• D. 10.0 N/m²

Answer: (C)

To determine the correct answer, it is important to understand the relationship between force, pressure, and area. Pressure is defined as the force applied per unit area. The formula used is: \[ \text{Pressure} = \frac{\text{Force}}{\text{Area}} \] In this scenario, the force applied is given as 100 kPa, which is equivalent to 100,000 N/m² (since 1 kPa = 1,000 N/m²). Next, we need to calculate the area of the plunger that the force is acting upon. The diameter of the plunger is provided as 4 cm, which can be converted to meters for standard unit consistency (4 cm = 0.04 m). The radius is then half of the diameter: \[ r = \frac{0.04 \text{ m}}{2} = 0.02 \text{ m} \] The area of a circle is calculated using the formula: \[ \text{Area} = \pi r^2 \] Substituting the radius into the formula gives: \[ \text{Area} = \pi (0.02 \text{ m})

To determine the correct answer, it is important to understand the relationship between force, pressure, and area. Pressure is defined as the force applied per unit area. The formula used is:

[

\text{Pressure} = \frac{\text{Force}}{\text{Area}}

]

In this scenario, the force applied is given as 100 kPa, which is equivalent to 100,000 N/m² (since 1 kPa = 1,000 N/m²). Next, we need to calculate the area of the plunger that the force is acting upon.

The diameter of the plunger is provided as 4 cm, which can be converted to meters for standard unit consistency (4 cm = 0.04 m). The radius is then half of the diameter:

[

r = \frac{0.04 \text{ m}}{2} = 0.02 \text{ m}

]

The area of a circle is calculated using the formula:

[

\text{Area} = \pi r^2

]

Substituting the radius into the formula gives:

[

\text{Area} = \pi (0.02 \text{ m})