IDK Flashcards
describe the specific heat capacity practical (how to find the shc of a material)
First place will be corner balance and press zero next at the oil to the beaker and record the mass of the oil then place it thermometer and an immersion heater into the oil with the starting temperature of the oil and wrapped a beaker in insulating foam to reduce thermal energy transferred to the surroundings. Then connect a jewel meter and a power pack to the immersion heater that’s how many joules of electricity pass into the immersion heater. leave for 30 mins to allow temp to rise so we can accurately read on the thermometer next total the amount of energy to pass into the joule meter and read the final temperature of the oil you can then calculate the specific heat capacity by rearranging the formula.
What are some sources of inaccuracy with the shc practical
Thermal energy passing out of the beaker into the air- to combat this use an insulated with a lower thermal conductivity
Not all thermal energy passing into the oil to stop this ensure the immersion heater is fully submerged
An incorrect reading of the thermometer can be stopped by using an electronic temperature probe
To reduce the error of thermal energy not being spread through the oil you should stir the oil
How is electricity sent through the National grid?
Step up transformers increase potential difference from power stations in order to reduce the energy loss in the transmission cables step down transformer is reduce the potential difference before the electricity passes to homes
How are electrons moved form one insulator to another when rubbed together.- this. is static electricity btwwwww
When you rub an insulator onto another insulator insulator concerning electrons Moussa is electrons over to the other insulator for example of plastic rod moves its electrons to a cloth win this then makes the plastic rod positive and the cloth negative.
what does the variable resistor do
variable resistors do not have a fixed value – they can change their value as the current changes.
How to calculate the total current in a parralel circuit
add all of the different branches of current up
how do U calculate potential diff in series circuits/ parallel circuits
it is shared throughout the circuit/ it is kinda weird but basically its just the same per lane but is split into components in those lanes like a series circuit
What is Nuclear fission?
In some elements the nucleus is large and unstable for example uranium and plutonium . in nuclear fission the nucleus of these elements split- typically by the nucleus absorbing a neutron. When this happens this triggers the nucleus to undergo fission in other words to split. When the nucleus splits it forms to smaller daughter nuclei roughly equal in size along with two or three neutrons, some gamma radiation and energy. All of the fission products have kinetic energy. The neutrons can now be absorbed by more uranium nuclei and trigger fission again and so on. - Know as a chain reaction
What Are controlled and uncontrolled fission chain reaction is used for.
Controlled- for realising energy in a nuclear reactor
Uncontrolled- da big bomb tings
What is Nuclear Fusion?
A nuclear fusion to light nuclei such as hydrogen are joined to form a heavier nucleus.
Some of the mass of the nuclei can be with can be converted into energy which is released as radiation.
atomic history- if ur bored its dumb and nobody cares
In ancient Greece they believed that everything was made of atoms they also believed that atoms are tiny spheres that cannot be divided.
In 1897 scientists discovered that atoms contain tiny negative particles they called these electrons. This shows the atoms are not spheres that cannot be divided and that atoms have an internal structure.
I’m putting put the plum pudding model was that made it was believed to be a ball of positive charge containing just electrons.
they then did the Alpha scattering experiment which proved that the plum pudding model was incorrect.
We now call the central part of the atom the nucleus and created the nuclear model.
What is specific latent heat- SLH
Specific latent heat of the substance is the amount of energy required to change the state of 1 kg of the substance with no change in temperature.
What is the specific latent heat of fusion
The same as the specific latent heat except it’s just from 1 kg of a substance from a solid to a liquid.
It is the specific latent heat of vaporisation
It’s the same as the specific latent heat of fusion except is the energy required to change 1 kg of the substance from a liquid to a vapour
What is DC
THE CURRENT FROM A CELL IS A DIRECT CURRENT SITE FROM POSITIVE TO NEGATIVE as the electrons only move in One Direction
What is AC and what is its main benefit
Electricity in the UK is an alternating current. Main benefit is that it is very easy to use a transformer to increase or decrease the potential difference this is why we use it in the UK frequency of 50 Hz and a potential difference of around 230 V it takes about 0.1 seconds for it to change direction and 0.2 seconds per cycle
How to do alpha decay calculations
During alpha decay the top number typically the larger one gets increased by four and the bottom number, typically the smaller one is reduced by two this gives you the numbers for the other element
How to do Beta decay calculations
Add the small add one to the smaller number on the left and do nothing to the top number page decay is electron so it’s zero on the top and -1 the bottom
How to do gamma decay equations
Both the atomic number and mass number are not changed