physics paper one

energy stores

thermal, kinetic energy, gravitational potential, elastic potential, chemical , magnetic, electrostatic and nuclear

kinetic energy

energy of a moving object

gravitational potential energy

energy stored due to an objects position in a gravitational field

power and efficiency

power is the rate at which energy is transferred or work is done. Measured in Watts. power is energy over time

efficiency is the useful output energy over the total power input

how is charge flow measured

coulombs. charge is current multiplied by time (s)

potential difference

voltage. Voltage is current multiplied by resistance

resistance measured in

Ohms

circuit rules (series vs Parallel)

series circuits have the same current everywhere and the total potential difference is shared between components

in a parallel circuit the total current is shared across branches. potential difference is the same across each branch and total resistance of two resistors is parallel is less than the resistance of the smallest individual resistor

density

mass per unit volume measured in kilos per m squared

density is mass over volume

specific heat capacity

energy needed to raise the temperature of one kilo of a substance by one degree

alpha

helium nucleus(two pro two nu) highly ioinizing weekly penetrating and can be stopped by paper

beta

fast moving electron. moderately ionising and penetrating stopped by aluminium

gamma

high frequency electromagnetic wave. weakly ionising highly penetrating and can be reduced by thick lead

half life

time taken for the number of radioactive nuclei in a sample to halve or the time taken for the count rate to drop to half the starting amount

specific heat capacity required practical

1. place a beaker on a balance and press zero

2. add oil to beaker

3. place thermometer and immersion heater into the oil

4. read the starting temperature of the oil

5. insulate the beaker to reduce thermal energy transfer to the surrounding

6. measure the temperature every thirty seconds and calculate the highest temperature and temperature change