GED Science TestPhysical ScienceEasy
A student is investigating the properties of a spring. They hang various masses from the spring and measure its extension. They find that a 0.5 kg mass causes the spring to extend by 0.1 meters. According to Hooke's Law, what is the spring constant (k) of this spring?
- A500 N/m
- B0.05 N/m
- C50 N/m
- D5 N/m
Show answer & explanationAnswer & explanation
Correct answer: C. 50 N/m
Hooke's Law states F = kx, where F is the applied force, k is the spring constant, and x is the extension. The force due to gravity is F = mg. Therefore, k = mg/x = (0.5 kg * 9.8 m/s²) / 0.1 m = 49 N/m, which is approximately 50 N/m.
Why the other options are wrong
- A. This value is too large, likely resulting from incorrect multiplication or division.
- B. This value would result if the mass was divided by the extension, without considering gravity.
- D. This value would result if gravity was not considered (0.5/0.1) or if incorrect units were used.
Hooke's Law
Hooke's Law states that the force (F) needed to extend or compress a spring by some distance (x) is proportional to that distance, where k is the spring constant.
- F = kx
- k is the spring constant, a measure of the spring's stiffness
- x is the extension or compression distance
Memory trick: Hooke's Hook holds the spring's stretch.