PAPER 1 - practice questions Flashcards
describe the energy transfer of a falling object, pendulum, catapolt
- gpe decreases
- kinetic increases
- heat energy dissipated into surroundings
describe the energy transfer of a car driving uphill
- chemical converts to kinetic
- this used to increase gpe to over come friction and air resistance
a nylon fleece (socks on carpet/nylon rod and cloth) is pulled over a student’s head as they take it off. he gets a small electric shock. explain why
- when the fleece is taken off its rubbed against another material
- this is friction
- therefore electrons have moved from one material to the other causing it to become charged
explain the difference between current supplied by mains and current supplied by battery
- battery - direct current - flows in one direction
- mains - alternating - constantly changing direction
touching a live wire is dangerous when connected to mains electricity supply. explain why
- pd of live wire is 230v
- human pd is 0v
- this means a large pd between wire and person so current flows through their body
why are step-up transformers used in the national grid
- Increase PD and decrease the current
- reduces energy loss and increases the efficiency of the transmition
identify properties of a gas
- fill a container
- little forces of a attraction between molecules so free to move
- low density and can be compressed
explain how properties of alpha radiation affect the level of hazard at different distances
- least penetrating because because unable to pass through sheet of paper (cant get through skin)
- shortest range in air as can only travel a few cm
- most ionising so the most dangerous in a short range
- at a long range not dangerous
what happens when you rub an acetate rod with a cloth in terms of electrons - STATIC
- the negative electrons move from the rod to the cloth
- this makes the cloth have a negative charge
and the rob have a positive charge because it has lost its electrons
the internal energy of a tyre increases when its inflated. explain why
- bc work is done on the air in the tyre
- so the temp of this air increases therefore the internal energy has increased
as someone moves down a zip wire their imcrease in kinetic energy was less than their decrease in gpe. explain why
- because the air resistance or friction causes thermal energy to be transferred to surroundings
explain and give examples of a RANDOM error
- caused by huamns
- measuring
- rounding
- estimating
- repeating and finding a mean will solve this
explain and give examples of a SYSTEMATIC error
- wrong answer every single time
- repeating this multiple times wont make this error change
explain and give examples of a ZERO error
- a systematic error caused by using equipment that isn’t zeroed properly
- eg a balance already has a mass of 1g before you measuring things on it
explain the advantage of radioactive waste having a short half life
- activity decreases fast
- so risk of harm decreases fast
