Ch 1 Physical Quantities and Units# Flashcards
All physical quantities consist of __________ and ___________.
numerical magnitude and unit
What are the 6 base quantities?
mass, length, time, current, temperature and amount of substance
What is the SI unit of mass?
kilogram (kg)
What is the SI unit of length?
meter (m)
What is the SI unit of time?
second (s)
What is the SI unit of current?
ampere (A)
What is the SI unit of temperature?
kelvin (K)
What is the SI unit of speed?
meters per second (m/s)
What is the SI unit of acceleration?
meters per square second (m/s2)
What is the SI unit of density?
kilogram per cubic meter (kg/m3)
What is a scalar quantity?
A quantity with only magnitude.
What is a vector quantity?
A quantity with both magnitude and direction.
Convert 0.001 m to mm.
What does the prefix ‘m’ represents?
1 mm
Convert 300 g to kg.
What does the prefix ‘k’ represents?
0.3 kg
Convert 0.00001 m to µm.
What does the prefix ‘µ’ represents?
10 µm
Convert 200 000 W to MW.
What does the prefix ‘M’ represents?
0.2 MW
Convert 20 000 000 J to GJ.
What does the prefix ‘G’ represents?
0.02 GJ
Convert this number to standard form:
0.003
Stardard form is a way of writing numbers in which a number between 1 to 10 is multiplied by an appropiate power of 10.
See picture for an example.
3.0 x 10-3
Give one example of a vector quantity.
Any of the following is correct:
velocity, acceleration, force, displacement, weight.
This list is not exhaustive.
Give one example of a scalar quantity.
Any of the following is correct:
speed, distance, time, mass, current, voltage, resistance etc.
This list is not exhaustive.
What are the 4 instruments used to measure length?
1) meter rule
2) measuring tape
3) digital caliper
4) digital micrometer
Each instrument has its own precision ( the smallest unit the instrument can measure) and can to use to measure a wide variety of length.
What is the smallest division of a measuring tape?
0.1 cm
What is the smallest division of a meter rule?
0.1 cm
What is the smallest division of a digital calipers?
0.001 cm
What is the smallest division of a digital micrometer?
0.001 mm
What is parallax error?
An error when the eye is not positioned in a line of sight perpendicular to the measurement readings.
What are the two types of observational errors?
random error and systematic error
What is a random error?
Random error varies unpredicatbly for different measurements.
What is a systematic error?
Systematic error is constant and not random. The error value is always the same for every measurement.
What is an oscillation?
A complete to-and-fro motion.
What does it mean by ‘the period of simple pendulum’?
The time taken by the pendulum to complete one oscillation.
