2022 Past Paper (Higher) Flashcards
Suggest two reasons why wind power was not able to meet demands
- wind turbines don’t turn when
the wind is too strong/weak - there are not enough wind
turbines (in the UK)
Explain how oiling would affect the efficiency of the wind turbine.
the efficiency would increase
because the percentage /
proportion / amount of energy
usefully transferred would
increase
Explain why people should be encouraged to use energy efficient electrical devices
more efficient devices waste
less energy
which would minimise the
electricity / energy demand
Describe a method the student could use to determine the density of the rock
measure mass using a balance / scales
* part fill a measuring cylinder with water and measure initial
volume
* place rock in water and measure final volume
* volume of rock = final volume − initial volume
* fill a displacement / eureka can with water level with spout
* place rock in water and collect displaced water
* measuring cylinder used to determine volume of displaced water
* volume of rock = volume of displaced water
*
* use mass and volume to calculate density
● use of: density = mass/
volume
Explain why taking the measurements more than once may improve the accuracy of
the density value.
a mean can be calculated
which reduces the effect of
random errors
What equation links current (I), potential difference (V) and power (P)?
P = V × I
What equation links efficiency, total power input and useful power output?
efficiency =
useful power output/
total power input
Thermometer A (non digital) is more likely to be misread.
Give one reason why
viewing angle affects
measurement
how does thermal conductivity relate to temp decrease and why?
temperature decrease in
a shorter time means a higher
thermal conductivity
(because) the rate of energy
transfer is higher
A student rubbed a plastic rod with a cloth. box
The rod became negatively charged and the cloth became positively charged.
0 5 . 1 Explain why the cloth became positively charged.
electrons transferred from the cloth (to the rod)
electrons are negatively charged
(so) there are more positive
charges than negative charges
on the cloth
Figure 6 shows the negatively charged rod on a balance.
Figure 7 shows another charged rod being held stationary above the rod on the
balance.
The rods do not touch each other
Explain why the reading on the balance increases.
there is an additional
(downwards) force on the
balance (increasing the mass
reading)
(because) the (held) rod is
negatively charged
(and rods with) like charges
repel
A negatively charged rod is held near an earthed conductor.
Explain why a spark jumps between the negatively charged rod and the earthed
conductor.
the (large) potential difference
between the two objects
(causes negative) electrons /
charges to move
(from the rod) to the conductor
Explain why transformer X is used in the National Grid
transformer X increases
potential difference
and decreases current
reducing (thermal) energy
transfer to surroundings
Explain why transformer Y is used in the National Grid.
transformer Y decreases the
potential difference
to a safe / safer value
What does an alpha particle consist of?
two protons and two neutrons