Chapter 2: Physical properties of matter Flashcards
What is the difference between the physical properties of strength and hardness?
Strength of a material is its ability to support a heavy load without breaking or tearing. E.g.(Steel)
Hardness of a material is its ability to withstand scratches and its ability to cut and scratch other materials (e.g. diamond)
What is a physical quantity?
A physical quantity is a quantity that can be measured and it consists of a numerical magnitude and a unit.
Student A has a height of 170cm. Identify which is the physical quantity, numerical magnitude and unit in the statement.
Physical quantity—height
Numerical Magnitude— 170
Unit—cm
What is the SI unit for length?
SI base unit—metre
Symbol of unit—m
What is the difference between systematic errors and random errors?
Systematic errors— always positive or always negative (fixed direction), consistent, e.g. zero errors on vernier calipers
Random errors— equal chance of being positive or negative (varying direction) with varying magnitudes, unpredictable e.g. human reaction time when using stopwatch.
What is the difference between accuracy and precision?
The accuracy of a measurement refers to how close it is to the true or accepted value.
The precision of a group of measurements refers to how close they are to each other.
The higher the density the higher the objects floats.
True or false?
False.
The higher the density, the more the objects sinks.
The lower the density, the higher the objects floats.
For a floating object, the greater the difference in density between the object and liquid, the higher the object will float. True of false?
True
How do you measure time using a digital stopwatch?
Smallest division 0.01s, record as shown for digital instruments.
What is the definition of parallax error and how should one refine the error?
Parallax error is an error in measurement due to the eye not being in the correct position when taking a reading. For accurate measurements, the eye must be positioned vertically above the mark to be read.
How can the volume of a sugar cube be determined using the displacement method above?
The volume of a sugar cube cannot be determined using the displacement method above. As the sugar cube will dissolved in the water and therefore not be able to get the difference in the volume of water before putting the sugar cube and after putting it. So, we should use oil or a solvent that sugar does not dissolve in for the volume displacement method.
What is milli in simple explanation?
1milli=0.1cm
1m=1000mm
What is one deci
One deci is 10cm
What is one kilo?
One kilo is 1000m.
Which length is the shortest?
A 0.02km
B 20dm
C 2000cm
D 20 000mm
B
