Question

A spring 20cm long is stretched to 25cm by a load of 50N; what will be its length when stretched by 100N, assuming that the elastic limit is not reached?

Answer 1

To solve this problem, we can use Hooke's Law which states that the extension of a spring is directly proportional to the force applied to it, as long as the elastic limit is not reached.

Hooke's Law formula: F = kx

Where:
F = force applied (N)
k = spring constant
x = extension of the spring (m)

First, we need to find the spring constant (k) using the given information:
50N = k(25cm - 20cm)
50N = 5k
k = 10 N/cm

Now we can use Hooke's Law to find the extension of the spring when a force of 100N is applied:
100N = 10 N/cm * x
x = 10 cm

Therefore, the length of the spring when stretched by 100N will be:
20 cm + 10 cm = 30 cm.