Physics Flashcards
Length
Length is the distance between two points
Si units- metres
Sub units-kilometeres centimetres and millimetres
Apparatus used for measuring length
Rulers tape measures vernier calipers and micrometer screw gauge
What is mass
Refers to the quantity of matter in an object
Subunits – g mg SI- kg
Apparatus used to measure mass
Beam balance
Weight
This is a measure of gravity
Weight is a force
SI units newtons
Apparatus to measure weight
Spring balance
Volume
This is the amount of space occupied by an object
SI units – M3
How is volume of liquids measured
Measured by using a measuring cylinder.
Volume of irregular objects
We use the method called displacement for finding volume of irregular objects. Displacement is when you put a rope with a rope attached to it and when you put it from the original mi length you minus the new lungs and that is the volume of your object.
Best possible displacement using a Eureka can which is when you fill the Eureka Karen with water and then position the measuring the spout emergently the irregular object water collected on is the volume of the irregular object
What is the area
Area is s surface covered by an object
What is density
Refers to mass per unit volume
SI units – kg or metres cubed
Subunits - g or cm cubed
Triangle for density
Mass/
Density X volume.
Why are objects that float is water less dense
Objects which float in water is said to be less dense. A brass casings in water because it’s more than 4 but a brass key tied to a piece of wood floats because combined density of wood and glass is less than denser water.
What is a force
The first to push pull or a twist
SI unit - newtons
What are the effects of forses
Forces can increase decrease or stop movement
Forces can change direction of movement
Forces can change the stored shape of an object
Types of forces
Contact forces
non-contact forces
Contact forces
Forces which act between objects which are physically touching
This was the reaction force; this is a force experienced by objects resting on a surface
Tension; force experienced by stretched object
Friction- force which opposes motion between rubbing surfaces
Air resistance; force resting on a motion of an object moving in air
Non-contact forces
Forces which act on objects are not touching
Example of this force include magnetic force; is the force experienced by magnets
Electrostatic force
Gravitational force this is force experienced by mass in gravitational fields.
Friction
This is a force that acts between solid surfaces.in fluids this is called drag.
Methods to reduce friction
Lubrication
Stream lining
Smoothing surfaces
Using ball bearings
Spring
Springs are elastic material with no elastic potential energy and mechanical energy
They can be compressed and they can be extended
Plastic materials don’t work in the original shape and length
Elastic material regain the shape when force acting on is withdrawn
Resultant force
This is a single force that is worth all forces acting on a body. Resultant force determines the direction which object will move magnitude of final fours which letter word can also be called net force and forces can combine to form balanced and unbalanced forces.
Balanced forces
They combine in such a way that they cancel out each other for example book on a table
Unbalanced forces
They combine in such a way that there is a resultant force for example in tug of war. Resultant force can be calculated by either addition or subtraction.
Please can I have a combined in series or parallel
In series extension is twice the extension in parallel but if the acceleration in the series was 10 cm extension in the parallel would be 5 / 2
Motion
Travel graphs arman distance time graphs and speed time graphs
Distance triangle
Distance
Time X speed
