Materials

Question 1

forces that produce extension

Answer 1

tensile forces

Question 2

describe a force against extension graph

Answer 2

straight line until elastic limit, where the spring undergoes elastic deformation and can return to its original length when force is removed.

Question 3

plastic deformation

Answer 3

permanent structural changes spring wont return to original length

Question 4

hooke’s law

Answer 4

the extension of the spring is directly proportional to the force applied as long as the elastic limit isnt surpassed.

Question 5

force constant

Answer 5

stiffness of the spring, gradient of force-extension graph

Question 6

hookes law experiment

Answer 6

• attach spring to clamp, set up metre rule
• suspend slotted masses from the sprign and record it
• improve accuracy by using a set square + reading it eye level to reduce parallax errors

Question 7

work done on a spring

Answer 7

w = fx

Question 8

work done from f-x graph

Answer 8

area under

Question 9

elastic potential energy

Answer 9

1/2Fx^2 + area under f-x graph

Question 10

rubber band work done

Answer 10

more work done stretching the band than when the exttension decreases. graph looks like a loop.

Question 11

polythene

Answer 11

does not obey hookes law

Question 12

stress

Answer 12

force/cross sectional area

Question 13

strain

Answer 13

extension/original length

Question 14

Ultimate tensile strength

Answer 14

max stress a material withstand before a material breaks

Question 15

young modulus

Answer 15

stress/strain ratio in N/m^2 or Pa, gradient of a stress-strain graph

Question 16

young modulus experiment

Answer 16

• measure the diameter with micrometer of the wire, apply varioud loads and measure length
• wear eye protection