What is the formula used to express Hooke's Law?

• A. F = mv²
• B. F = kx
• C. F = ma
• D. F = pA

Answer: (B)

Hooke's Law describes the relationship between the force applied to a spring and the displacement or stretch of that spring. The correct formula, which is F = kx, encapsulates this principle, where F represents the force exerted by the spring, k is the spring constant (a measure of how stiff the spring is), and x is the displacement from the spring's equilibrium position.

When a spring is either compressed or stretched, it exerts a force that is directly proportional to that displacement. This direct proportionality is what is captured in Hooke’s Law. The larger the displacement (either stretching or compressing), the greater the force the spring will exert in the opposite direction, aiming to return to its original length.

The other formulas listed are associated with different physical principles: the equation involving mv² relates to kinetic energy, F = ma defines Newton's second law of motion (force equals mass times acceleration), and F = pA is used in fluid mechanics to express the force exerted by a fluid in terms of pressure and area. These formulas pertain to different phenomena and do not describe the restorative force of springs like Hooke's Law does.