build a spring balance

Name ___________________________

Building a Spring Balance

First, build a spring balance like the one shown above.

Your task is to calibrate the balance so that you can measure some unknown masses.

Paper FastenerThick Card

Elastic Band

Card Pointer

String or thread

‘Hook’ made from paper clip

Paper clip

0

0

1

0

1

1. Mark zero on the card

2. Add 100 g mass and mark 1

3. Use a ruler to divide 0 and 1 into smaller, regular ‘bits’: e.g 4 or 5 smaller sections

4. Use a ruler to divide the space between 0 and 1 into smaller, regular ‘bits’: e.g 4 or 5 smaller sections

5. Repeat until there is no more space on the card.

6. Label the scale “Weight in newtons, N”.

Questions:

a) What ‘C’ have you been doing to the scale?

b) What is one of small lines on the scale equal to? (Hint: Could be ½, ¼ or 0.2 N – you decide!)

c) Use your scale to weigh and unknown weight e.g. an apple. Write it down.

d) Use a manufactured scale to check your scale.

e) Is your scale reasonably accurate?