Physics Innit Flashcards
The main renewable energy sources are:
Wind
Solar
Geothermal
Water waves
Biofuels
Hydro-electricity
Tidal
Strongly ionising:
Alpha
Moderately ionising:
Beta
Earth wire:
Yellow/green
Safety wire to stop the appliance becoming live
Three cons of nuclear power:
Very expensive to build
Risk of a nuclear meltdown
The waste is radioactive and very expensive to store
Neutral wire
Blue
Completes the circuit
Three cons of solar and wind power
Relatively high upfront costs
Their power production is dependent on the weather and therefore inconsistent
Take up alot of land space
What is the equation for wave speed?
Wave speed = frequency × wavelength
What is the equation for GPE?
Mgh
Resistance practical:
Tape-metre ruler-wire
Move the clips further apart to increase the lengths of the wire in the circuit. Measure the resistance.
What is the equation for charge flow?
Charge flow = current x time
(Q=it)
Density practical
Density=m/v
Density tells us the mass for a given volume
Regular objects
Determine mass using balance
To work out the volume, use a ruler and measure the length of the sides. Volume = length of the side ³. Put it in the equation
Irregular objects
Mass using balance
Fill eureka can using water, put a measuring cylinder under the spout.
Place object in water, it will cause water to be displaced and flow out from the spout.
Measure rhe volume of the water displaced. Same as volume of the object
What is gravity and what properties affect the strength of gravitational attraction?
Gravity is the force of attraction between 2 objects.
Two factors that affect the strength are:
The mass of the two objects
The distance between the two objects
What are the disadvantages of biofuels?
They require a large area of land to grow
They require a lot of energy to harvest, process and transport.
Weakly ionising
Gamma
What is the equation for potential difference?
Current x resistance
(V = IR)
What are the main pros of nuclear power
Nuclear fuels such as plutonium and uranium are relatively cheap
Nuclear power plants can produce large and steady electric power
Nuclear power does not produce any greenhouse gases
Charge and mass of a proton
Charge = +1
Mass = 1
Charge and mass of a neutron
Charge = 0
Mass = 1
Live wire
Brown
Provides the alternating potential difference from the supply
What is the equation for power?
(Resitance)
Power = (current)² x resistance
P= I²r
What is the equation for power?
Work done/time taken
Energy transferred/time taken
What is the equation for kinetic energy?
1/2 x mass x speed² (v²)
Thermal insulation practical
Place small beaker into larger beaker
Kettle boil water, transfer 7
80cm³ of hot water into small beaker
Place a piece of cardboard as a lid for the beakers, but leave a hole in the middle for the thermometer
Thermometer into the hole
Record starting temperature and start stopwatch
Record temp every 3 mins for 15 mins
Repeat same using volume of hot water, however this time use insulating materials to fill the gap between the beakers. Use the same mass in each case.
Record in table + cooking curces for differential.
Thickness affects thermal insulation
Beaker 80cm³, hot water, measure every 3 mins for 15.
Repeat but for 2 layers of newspaper around the beaker, Repeat again 2 more times using 4 and 6 layers
