Springs and Elasticity Flashcards
7 cards from real Bennett Mechanical Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Springs and Elasticity flashcards as text
According to Hooke's Law, when the force applied to a spring is doubled, what happens to its extension?
Answer: It doubles
Hooke's Law states that extension is directly proportional to applied force (F = kx), so doubling the force doubles the extension.
A spring has a spring constant of 50 N/m. How much force is needed to stretch it 0.2 meters?
Answer: 10 N
Using F = kx: F = 50 N/m × 0.2 m = 10 N.
Two identical springs connected in series (end to end) will have what effective spring constant compared to one spring?
Answer: Half as stiff
Springs in series share the same force, but each stretches, so total extension doubles and effective spring constant is halved.
What is the SI unit of the spring constant?
Answer: Newtons per meter (N/m)
Spring constant k = F/x, so its unit is force divided by distance, which is Newtons per meter (N/m).
Which material property describes a material's ability to return to its original shape after being deformed?
Answer: Elasticity
Elasticity is the property that allows a material to recover its original shape and size after the deforming force is removed.
The elastic potential energy stored in a spring with spring constant k compressed by distance x is:
Answer: ½kx²
The potential energy stored in a spring is PE = ½kx², derived from integrating the force over the displacement.
When two identical springs are connected in parallel (side by side, sharing the same endpoints), the effective spring constant is:
Answer: Twice the single spring constant
Springs in parallel each share the load and deflect equally, so their spring constants add together, giving twice the stiffness.