3.1.2.
A wire is non-uniform, its diameter varies along its length. Random or systematic
error?
- systematic ← obvious pattern/bias in the differences
Resolution of micrometer?
- 0.01mm
How to read off a micrometer?
→ big scale shows 4 mm
→ small scale shows 0.06mm
→ 4 + 0.06 = 4.06mm
How to use a micrometer?
Resolution of vernier calliper?
- 0.1mm
How to read off a vernier calliper?
, Difference between a spring balance, lever balance and top pan balance?
- order of precision:
spring < lever < top-pan
Use of set squares?
- to draw perpendicular lines, angles
What is an oscilloscope?
- a device for viewing oscillations by a display on the screen of a cathode ray tube
How to prevent parallax errors?
→ the pointer is where we need to read off the ruler
→ the mirror ensures that we are reading it off at the right place
How to ensure that our metre ruler is vertical?
- set square perpendicular to the ruler and the bench
(we assume bench is horizontal)
OR
- attach a small weight to a string - called a plumb line
- see if ruler is parallel to plumb line from 2 perpendicular directions
How to ensure that our metre ruler is horizontal?
- use a set square to align the metre ruler perpendicular to a vertical metre ruler
Adv. of calibrating equipment?
- reduces chance of zero errors
Precision of single measurement?
Precision for multiple measurements?
A wire is non-uniform, its diameter varies along its length. Random or systematic
error?
- systematic ← obvious pattern/bias in the differences
Resolution of micrometer?
- 0.01mm
How to read off a micrometer?
→ big scale shows 4 mm
→ small scale shows 0.06mm
→ 4 + 0.06 = 4.06mm
How to use a micrometer?
Resolution of vernier calliper?
- 0.1mm
How to read off a vernier calliper?
, Difference between a spring balance, lever balance and top pan balance?
- order of precision:
spring < lever < top-pan
Use of set squares?
- to draw perpendicular lines, angles
What is an oscilloscope?
- a device for viewing oscillations by a display on the screen of a cathode ray tube
How to prevent parallax errors?
→ the pointer is where we need to read off the ruler
→ the mirror ensures that we are reading it off at the right place
How to ensure that our metre ruler is vertical?
- set square perpendicular to the ruler and the bench
(we assume bench is horizontal)
OR
- attach a small weight to a string - called a plumb line
- see if ruler is parallel to plumb line from 2 perpendicular directions
How to ensure that our metre ruler is horizontal?
- use a set square to align the metre ruler perpendicular to a vertical metre ruler
Adv. of calibrating equipment?
- reduces chance of zero errors
Precision of single measurement?
Precision for multiple measurements?
