9.5 the scientist Flashcards
list the different types of energy
thermal chemical kinetic nuclear elastic /strain gravitational potential
the 4 ways energy can be transferred
Mechanically - By the action of a force.
Electrically - By an electrical current.
By radiation - By Light waves or Sound waves.
By heating - By conduction, convection or radiation.
how do we reduce friction
use lubricant
work: equation
force (N) x distant (M)
power (w) = work done (j)/ ?
power (watt) = work done (j)/ time (s)
charge (C): equation
current (amps) x time (s)
energy transferred (j): equation
charge (Coulombs) x potential difference (volts)
energy (j): equation
current (amps) x potential difference (volts) x time (s)
power(w) = ? x voltage
power(w) = current x voltage (PIV)
power = ? X resistance
power = current^2 X resistance
GPE(j): equation
mass x height x g
KE(j): equation
1/2 x mass x velocity^2
where does conduction, convection and radiation take place?
conduction- solids
convections- fluids
radiation- w/o particles, em waves
what does insulating mean
doesnt pass energy on
why do we use lubricants
to reduce friction, which reduces the amount of thermal energy that is lost
what do periods tell us in a periodic table
the number of electron shells in an atom
what do groups tell us in a periodic table
the number of electrons in the outer shell
what can graphite be used for and why?
It is a good conductor of electricity. Its high conductivity makes it useful in electronic products because of the delocalised electrons which are free to move and carry an electronic current.
It can also be used as a lubricant because of the weak intermolecular forces which are slippery and can be easily overcome (requires little energy to remove)
what can diamonds be used for and why?
Because diamonds are very hard they are often used as an abrasive. Small particles of diamond are embedded in tools and these tools are then used for cutting, drilling, or grinding hard materials.
Diamonds are extremely hard because the outer electron shell of each carbon atom has four electrons, these electrons are shared with four other carbon atoms to form very strong covalent bonds.
how does an electric current flow?
when electrons move through a conductor
what is 1 amps equivalent to
1 coulomb per second
