A force of 2N stretches an elastic by 30mm. What additional force will be stretches the material 35mm? Assume that the elastic is not exceeded

To find the additional force needed to stretch the material by 35mm, we can use the formula:

Force = k * x

where:
k = spring constant
x = extension

First, let's calculate the spring constant using the initial force and extension:

2N = k * 30mm
k = 2N / 30mm
k = 0.067 N/mm

Now, we can use the spring constant to calculate the additional force needed to stretch the material by 35mm:

Force = 0.067 N/mm * 35mm
Force = 2.35N

Therefore, an additional force of 2.35N will be needed to stretch the material by 35mm.