Chapter 1: Measurement Flashcards
What is a physical quantity?
A physical quantity is a quantity that can be measured
What are the 10 common prefixes?
Tera Giga Mega Kilo Deci Centi Milli Micro Nano Pico
What are the 4 instruments used to measure length? State the length measurable and its precision.
Measuring Tape: More than 1m, 0.1cm
Metre Rule: Several cm to 1m, 0.1cm
Vernier Caliper, between 1 cm to 10cm, 0.01cm
Micrometre screw gauge, Less than 1cm, 0.001cm
When does parallax error occur?
When the eye/line of sight of the observer is not perpendicular to the mark of the scale
What are the 5 parts of a vernier caliper?
Internal jaws External jaws Main Scale Vernier Scale Tail
What are the 5 parts of a micrometre screw guage
Anvil Spindle Main Scale Thimble scale Ratchet
When do zero errors occur
Vernier calipers: Zero error occurs when the 0 on the main scale does not align with the vernier scale when the jaws are fully closed
Precautions to take before using the MSG
Make sure when when the anvil and spindle are in contact with each other that the 0’s on the thimber scale and main scale are aligned to avoid zero error.
What are examples of instruments to measure time
digital watch or analogue stopwatch and alarm clock
Define the period of a pendulum
It is the time take for a pendulum to make one complete oscillation
Why should we record the time for oscillations 10 times instead of one?
This is to reduce the error in measuring time due to human reaction time. Hence it will improve the accuracy of the results/measuring the period of the pendulum.
What are factors that affect the period
- Length of the thread/bob
2. Gravitational Field Strength
What are factors that do not affect the period?
- The Mass of the Bob
2. The amplitude of oscillation
