Springs

Question 1

What is Hooke’s Law?

Answer 1

Force is directly proportional to extension below the elastic limit.

Question 2

How would you use a force extension graph to measure the spring constant?

Answer 2

The spring constant is the gradient below the elastic limit.

Question 3

What is the formula for springs in series?

Answer 3

1/k =1/k1 + 1/k2

Question 4

What is the formula for springs in parallel?

Answer 4

k = k1 + k2

Question 5

What is the area under a force extension graph equal to?

Answer 5

The work done to stretch the material or the elastic potential energy stored in the material.

Question 6

Define tensile stress (σ) and what is its units?

Answer 6

Force per unit cross-sectional area.
Pascals

Question 7

Define tensile strain (ε) and what are its units?

Answer 7

Extension per unit original length.
No units

Question 8

Define Young Modulus

Answer 8

The ratio of stress to strain measured in Pascals.

Question 9

What is the gradient of a stress strain graph?

Answer 9

Young Modulus of the material.

Question 10

Define elastic behaviour of a spring

Answer 10

When the object returns to its original length when unloaded.

Question 11

Define plastic behaviour of a spring

Answer 11

When the object’s length is permanently changed. It will not return to its original shape when the load is removed.