Paper 2 Required practicals Flashcards
Elasticy PAG - Describe a suitable method
Hang a spring off a clamp stand
Measure the original length of the spring
Add a 1 N weigth and measure the final length of the spring with a ruler
Calcualte the extension (final length - original length)
Repeat for weights 2, 3, 4, 5 and 6 N
Elasticy PAG - State the variables and whether they are continuous, discrete or catergoric
Independent - Weight (continuous)
Dependent - Extension (continuous)
Control - Spring constant (continuous)
Elasticy PAG - What type of graph should you draw? Why?
Line - both variables are continuous
Elasticy PAG - Describe the expected results
Forces is directly proportional to extension as long as the elastic limit hasnt been passed.
The graph should be a straight line through the origin up to the elastic limit.
Elasticy PAG - What is the main cause of error and how can it be reduced?
Parallax error not having your eye level with the spring when measuring its extension.
Reduce this my placing a wooden splint horizontally at the bottom of the spring.
Elasticy PAG - Describe a suitable risk assessment
Clamp stand may topple - this could fall and hurt your foot - place a counter weigth on the base of the clamp to stop it toppling
Elasticy PAG - Describe elastically deformed
The object will return to its original length when all forces are removed
Elasticy PAG - Describe inelastically deformed
An object wont return its original length once all forces are removed, it has been permanently stretched.
Elasticy PAG - State Hooke’s law equation
Force (N) = Spring constant (N/m) x extension (m)
Elasticy PAG - how can the spring constant be found from a graph of force against extension
From the gradient
Newton’s second law PAG - state the relevant equation
Resultant Force (N) = mass (kg) x acceleration (m/s2)
Newton’s second law PAG - Describe a suitable method
Attached a piece of card of known length to a trolley.
Attached some string to the trolley running over a pulley.
Place a 1 N weigth on the end of the string and allow it to accelerate the trolley through two light gates.
Use the light gates to measure the acceleration of the trolley
Repeat for 2, 3, 4, 5 and 6 N
Newton’s second law PAG - State the variables and whether they are continuous, discrete or catergoric
Independent - Resultant force (continuous)
Dependent - Acceleration (continuous)
Control - mass of trolley (continuous), Material of surface (discrete)
Newton’s second law PAG - State the expected results
As resultant force increases the acceleration will increase. They are directly proportional to each other so the graph should be a straight line through the origin.
Newton’s second law PAG - Describe a risk assessment
Falling masses - could land on your feet - stand away from the experiment