Year 1 Physics Key Flashcards

What are SI units?

Base unit of all physical quantities

What is the SI Unit Acronym

SMACK A MOLE KELVIN

(second)(meter)(ampere)(candela)(kilogram) (Moles)

(Kelvin)

What is the SI Unit for Length

Metres

Whats is Electrical Current Measured In?

Amps

What is the SI unit used for Light intensity?

Candela

What is the SI Units for Mass?

Kilogram

What Quantity is Measured In Kelvin?

Temperature

what is Moles used to quantify

Amount of Substance

whats the SI unit of Force

Kg m s^-2 since F = M x A

SI Units of Energy

Kg m²s^-2

KE = ½ x Mass x Velocity

which power of 10 is Tera

10¹²

which power of 10 is Giga

10⁹

which power of 10 is Mega

10⁶

which power of 10 is Kilo

10³

which power of 10 is Centi

10^-2

which power of 10 is Milli

10^-3

which power of 10 is Micro

10^-6

which power of 10 is Nano

10^-9

which power of 10 is Pico

10^-12

which power of 10 is Femto

10^-15

What is a Anomaly?

Anomaly is a data point or value in a set of results which does not fit the trend of the data.

Whats is a systematic error

An error which occurs due to faulty equipment or experimental method. systematic error causes the results to differ by the same amount each time making it predictable.

What are 2 ways of reducing random errors

1. take atleast 3 repeats and calculate a mean (this decreases anamolies)

2. use higher resolution equipment

How can a systematic error be reduced?

By calibrating the apparatus before use.

What is precision

precision is is how consistant/close together data is, in a data set.

what is repeatable experiment?

Repeatable - If the original experimenter can redo the experiment wit the same equipment and method and get the same results

What is a reproducible experiment

Reproducible - if the experiment can be redone by a different person or different technique and same results are found

What is resolution?

Resolution is the smallest change in the quantity being measured like for e.g on a ruler 1mm

What is absolute uncertainty?

Absolute uncertainty is a uncertainty given as a fixed quantity

How to calculate absolute uncertainty on analog?

Analog + half the smallest division for a single reading (e.g 0.5mm for ruler)

How to calculate absolute uncertainty on digital?

digital + the smallest increment (e.g smallest increment being 0.1 then it has + 0.1 uncertainty)

How to calculate precentage uncertainty?

(Absolute uncertainty ÷ measured value) x 100 = % Uncertainty

How can fractional and percentage uncertainty be reduced

by measuring larger quantities.

(for e.g a longer rope will have smaller percentage uncertainty )

Difference between reading and measurements.

Reading - is one value found

Measurement - difference between two readings found.

whats the rule of uncertainty with a range of values

to find uncertainty with a range of values you do ( Max - min ) / 2

result = Mean of range + uncertainty

What is the order of magnitude?

Powers of ten which are used to measure how big an object is.

What is a scalar quantity

A quantity which only has magnitude.

What is a vector Quantity?

Vector quantity has Magnitude and Direction

How is speed calculated

Speed = Distance / time

ms^-1 = m / s

Define displacement

displacement of an object is the distance it has travelled in a certain direction.

What is velocity and what is the equation used to calculate velocity

Velocity is rate of change of displacement, or speed (Vector)

What is acceleration and how do you calculate it?

Acceleration is the rate of change of velocity (vector)

Acceleration(ms^-2) = change in velocity / time

understand this graph

yeah

What does the area under a velocity-time graph represent?

Displacement

What does the area under an acceleration-time graph represent?

Velocity

How to determine g practical

1. Have an electro magnet hold steel ball suspended over 2 light gates, when

2.the ball is electronically released

3 ball passes through the first light gate it will start timer and when it passes the 2nd gate it stops the timer

4. and data logger will display time taken to pass through the gate.

5.repeat step 1-3 but with different amount of light gate distances.

we use the equation s = ut + ½ at² (and you calculate a which is g)

a ball is projected off a castle at 6ms^-1 how does its horizontal velocity change from it’s launch until it hits the ground?

Horizontal velocity will remain the same as there is no acceleration in horizontal direction

In projectile motion what is vertical acceleration?

The vertical acceleration is equal to the gravitational field strength(g)

give 3 examples of common forces and what they do?

1. Friction is the force that arises when 2 surfaces rub against each other

2. Drag the resistive force on an object travelling through a fluid (e.g water or air)

3. Upthrust - the upward buoyancy force acting on an object when an object is in fluid

What is terminal velocity?

When forces acting on falling object become balanced so resultant force is 0

What is the principle of moments?

for an object in equilibrium, the sum of the clockwise moment is the sum of anti clockwise movements

What is a moment?

a turning force:
force x perpendicular
(perpendicular distance from the point to the line of action of the force)

What is a couple?

A pair of equal and opposite forces which have same magnitude but opposite direction.