Physics Past Paper 1 Flashcards
(18 cards)
What does direct proportional difference mean?
Potential difference that doesn’t change direction
Nuclear fusion is the joining together of ? . During nuclear fusion the total mass of particles ? .
Nuclei, decreases
Suggest two reasons models are tested before beginning to build nuclear fusion power stations
To make sure it is safe, to see if it is effective
Describe a method that you could do to measure how the current in a resistor at constant temperature varies with the potential difference across the resistor
-Measure current with ammeter
-Measure potential difference with volt meter
-Vary the resistance of the variable resistor
-Record range of potential differences and currents
-Reverse connections for negative results(repeat)
-Plots a graph of I against V
-Switch circuit off between measurements to keep temperature low
Explain how increased temperature of a resistor would affect results in an experiment
Graph would no longer be directly proportional because resistance of resistor is higher
A student only measured the volume of each fruit once when trying to find density. The volume measurements cannot be used to show that the method to measure volume gives precise readings, why?
Repeat readings, determined precision
Why is it unlikely that all of the electricity that the UK needs can be generated by solar power?
It is not always sunny in the UK so the solar panels wouldn’t work most of the time, lots of land would need solar panels
What is meant by random nature of radioactive decay?
Impossible to predict when a nucleus will decay
A polonium nucleus decayed by emitting an alpha particle and forming a lead nucleus, the lead nucleus then decay by emitting a beta particle and forms a Bismith nucleus, the Bismith nucleus then decayed by emitting a beta particle and forms a polonium nucleus. Explain how these three decay is result in a nucleus of the original element polonium.
First decay loses two protons, second and third decay gain one proton each, same proton number means same element
Explain how closing the switch would affect the current in the variable resistor
Current drops to 0 in variable resistor as switch has zero resistance
Why would a toy car need more energy to complete a loop in the toy track?
So the car still moves when in the loop
A teacher demonstrated the relationship between the pressure in a gas and the volume of the gas. Give one control variable in the investigation.
Mass of gas
When the volume of a gas in a syringe increases, the pressure on the inside walls of the syringe decreases why
Less frequent collisions between the particles and walls, lower force on syringes walls, pressure is force per unit area
What is the advantage of transmitting electricity at a very high potential difference?
Low current, less energy dissipated to surroundings, more efficient
Explain why a person could receive a fatal electric shock if they fly their kite close to but not touching a power cable
Electric field strength is high, the air acts as a conductor, string conducts current to person
Explain why the current in a steel wire is different to the current in a single aluminium wire
Potential difference across each wire would be the same, the wires have different resistances
A specific heat capacity of ice is less than the specific heat capacity of water. How is this shown in a graph?
Ice line would have a steep gradient, less energy is needed to raise the temperature by 1°C
The specific latent heat of fusion of ice is less than the specific latent heat of vaporisation of water. Explain how a graph could show this.
It would take less time for us to melt than the water to boil. Lesser energy transferred.
