AQA GCSE COMBINED SCIENCE TRILOGY
HIGHER TIER CHEMISTRY PAPER 2H
◉ What factors affect wind speed. Answer: Temperature
Atmospheric pressure
Any large buildings or structures nearby e.g. forests reduce wind
speed travelling through them
◉ Acceleration. Answer: change in velocity in a certain amount of
time
◉ Equation for Acceleration. Answer: Acceleration (m/s²) = Change
in Velocity (m/s) / Time (s)
a=Δv/t
◉ What is deceleration?. Answer: Negative acceleration - when
something slows down, the change in velocity is negative
◉ What is constant acceleration?. Answer: Uniform acceleration -
acceleration due to gravity is uniform for objects in free fall
,◉ Equation for Uniform Acceleration. Answer: Final velocity² (m/s)
- Initial velocity² (m/s) = 2 x Acceleration (m/s²) x Distance (m)
v²-u²=2as
◉ Distance-Time Graphs - Features. Answer: 1) Gradient = speed
2) Flat sections = object is stationary
3) Straight uphill sections = object is travelling at a steady speed
4) Curves = object is accelerating or decelerating
5) Steepening curve = object is speeding up
6) Levelling off curve = object is slowing down
◉ Velocity-Time Graphs - Features. Answer: 1) Gradient =
acceleration
2) Flat sections = object is travelling at a steady speed
3) Uphill sections = object is accelerating
4) Downhill sections = object is decelerating
5) Curves = object is changing acceleration
The steeper the graph, the greater the acceleration or deceleration
◉ What does friction do?. Answer: It causes objects to slow down
when they rub against another surface
, ◉ What is drag?. Answer: The resistance you get in a fluid
Air resistance is a type of drag
◉ How do you reduce drag?. Answer: Keep the shape of an object
streamlined
◉ process of a falling object. Answer: 1) When a falling object first
sets off, the force of gravity is much more than the frictional force
slowing it down, therefore the object accelerates
2) As the speed increases, the friction builds up
3) The acceleration is gradually reduced until eventually, the friction
force is equal to the accelerating force - the resultant force is 0
4) At this point, it will have reached maximum speed or terminal
velocity and will fall at a steady speed
◉ What determines the terminal velocity?. Answer: The terminal
velocity of any object is determined by its drag in comparison to its
weight
◉ In the last few metres of his descent during the parachute stage,
the person travels at a terminal velocity. Explain why (2). Answer: -
Because the drag had the same force on the parachuter as the weight
- weight pushes him down
- Drag/air resisance keeps him. Hes reached terminal velocity (2)
HIGHER TIER CHEMISTRY PAPER 2H
◉ What factors affect wind speed. Answer: Temperature
Atmospheric pressure
Any large buildings or structures nearby e.g. forests reduce wind
speed travelling through them
◉ Acceleration. Answer: change in velocity in a certain amount of
time
◉ Equation for Acceleration. Answer: Acceleration (m/s²) = Change
in Velocity (m/s) / Time (s)
a=Δv/t
◉ What is deceleration?. Answer: Negative acceleration - when
something slows down, the change in velocity is negative
◉ What is constant acceleration?. Answer: Uniform acceleration -
acceleration due to gravity is uniform for objects in free fall
,◉ Equation for Uniform Acceleration. Answer: Final velocity² (m/s)
- Initial velocity² (m/s) = 2 x Acceleration (m/s²) x Distance (m)
v²-u²=2as
◉ Distance-Time Graphs - Features. Answer: 1) Gradient = speed
2) Flat sections = object is stationary
3) Straight uphill sections = object is travelling at a steady speed
4) Curves = object is accelerating or decelerating
5) Steepening curve = object is speeding up
6) Levelling off curve = object is slowing down
◉ Velocity-Time Graphs - Features. Answer: 1) Gradient =
acceleration
2) Flat sections = object is travelling at a steady speed
3) Uphill sections = object is accelerating
4) Downhill sections = object is decelerating
5) Curves = object is changing acceleration
The steeper the graph, the greater the acceleration or deceleration
◉ What does friction do?. Answer: It causes objects to slow down
when they rub against another surface
, ◉ What is drag?. Answer: The resistance you get in a fluid
Air resistance is a type of drag
◉ How do you reduce drag?. Answer: Keep the shape of an object
streamlined
◉ process of a falling object. Answer: 1) When a falling object first
sets off, the force of gravity is much more than the frictional force
slowing it down, therefore the object accelerates
2) As the speed increases, the friction builds up
3) The acceleration is gradually reduced until eventually, the friction
force is equal to the accelerating force - the resultant force is 0
4) At this point, it will have reached maximum speed or terminal
velocity and will fall at a steady speed
◉ What determines the terminal velocity?. Answer: The terminal
velocity of any object is determined by its drag in comparison to its
weight
◉ In the last few metres of his descent during the parachute stage,
the person travels at a terminal velocity. Explain why (2). Answer: -
Because the drag had the same force on the parachuter as the weight
- weight pushes him down
- Drag/air resisance keeps him. Hes reached terminal velocity (2)
