What is a systematic error?
Errors of the same measurement in the same direction from the true value, following a pattern / trend / bias. It is “off” by a certain amount.
What is a random error
Errors of measurment of differing direction and magnitude around the mean value.
How to fix a systematic error?
Correct it via calculation.
How to fix a random error?
By finding the:
mean
removing anomalies
drawing a graph
When is a measurement accurate?
A measurement is accurate if it is close to the true value.
When is a measurement precise?
It is precise when there is very little spread about the mean value.
What is resolution?
Smallest change in the quanity being measured.
What does it mean by a greater resolution?
A better (i.e. smaller) resolution.
When is an experiment repeatable?
same method
same equipment
same result
same person
When is an experiment reproducable?
different person or and
different equipment and
same result
What is the radium of an atom?
1 × 10-10
What is the radius of the Earth?
1 × 107
What is the radius of the sun?
1 × 109
What is the radius of the whole universe?
1 × 1026
What is a scalar quantity?
Only has magnitude (size)
What is a vector quantity?
Has both magnitude (size) and direction
What are some examples of scalar quantites?
Temperature
Speed
Distance
What are some examples of vector quantites?
Velocity
Acceleration
Displacement
What is the distance of an object?
How an object travelled but not the direction
What is the displacement of an object?
How far an object is from where it started, and its direction
What is the rule for adding vectors in the same direction?
Add the size
Direction is the same
What is the rule for adding vectors in the opposite direction?
Subtract the smaller vector from the bigger one
Direction is the same as the biggest vector
How to find the size of 2D vectors?
Pythagoras
How to find the direction of 2D vectors?
Tan