Spring and Hooke's law Chapter 3

Question 1

What is the equation for young modulus?

Answer 1

Stress/ strain FL/AX

Question 2

What is the equation for stress?

Answer 2

force/area

Question 3

What is the equation for strain?

Answer 3

Extension / length

Question 4

For stress strain graph what does gradient represent? And how do you work it out?

Answer 4

-Youngs modulus
-Gradient

Question 5

Draw graph for optical fibre
-Explain why this graph is made?

Answer 5

Linear graph, straight line
-Because It will not stretch beyond elastic limit, it undergoes elastic deformation, then break
-OBEYS HOOKES LAW

Question 6

What does the area under force extension graph represent?

Answer 6

-Elastic potential energy

Question 7

Draw graph for Electrical wire, and explain why this is.

Answer 7

-Linear then bends at end.
-Wire is ductile it will undergo elastic deformation and go beyond elastic limit, then undergoes plastic deformation.
-OBEYS HOOKES LAWUNTIL POINT OF DEFORMATION

Question 8

Draw graph for Fishing line or rubber and explain why this is.

Answer 8

-S shaped line
-Fishing line and rubber are polymeric material and are elastic so they return to their original shape.
-DOES NOT OBEYS HOOKES LAW

Question 9

State Hooke’s law

Answer 9

-Extension of a spring is directly proportional to force applied, as long as elastic limit is not exceeded