❌ 10. Required Practical: Investigating Force And Acceleration (P10) Flashcards
Part 1 / 2: Investigating The Effect of Force on Acceleration RP - Safety Measures
- The pulley must be securely attached to the bench.
- Any masses on the trolley should be secure – stick them down if needed.
- Make sure no one is standing where the mass holder or masses could land on their feet.
- Make sure the trolley does not fall off the table – be ready to catch it if needed.
Part 1: The Effect of Force on Acceleration RP - Equipment
- Trolley
- Piece of card shaped like this:
- Ruler (30 cm is long enough)
- Sticky tape or tack
- Pulley with clamp
- Mass holder and 50 g masses
- Wooden block, or lump of modelling clay (if needed to protect pulley)
- String or strong thread
- Data logger
- Light gate, with connecting lead
- Clamp stand and clamp for light gate
Part 1: The Effect of Force on Acceleration RP - Method
- Measure the length of each card segment, and make a note of this.
- Set up the apparatus as shown in the diagram below. When the trolley is as close to the pulley as it can get, the bottom of the mass holder should be between 0.5 cm and 1 cm above the floor.
- During this experiment the trolley will travel towards the pulley. If you need to, place a lump of modelling clay or a block in front of the pulley to protect it from being hit by the trolley.
- Set up the data logger. You will use its measurements to find the trolley’s acceleration. There are different ways of doing this, depending on the data logger and the method your teacher asks you to use.
- Add masses to the mass holder so that the total mass, including the holder, is 250 g.
- Pull back the trolley, set the data logger to record, and then let the trolley run to the pulley. Collect the necessary measurements from the data logger.
- Take 50 g off the mass holder and place it onto the trolley. You may need to use a small amount of tape or sticky tack to hold the mass securely in place. Repeat step 6.
- Repeat steps 6–7 until there is 200 g on the trolley – this will be the fifth and final run.
- If you have time, measure acceleration twice for each amount of mass on the holder. Record both results in your table and calculate their mean average. This will give you a more reliable reading for each acceleration.
Part 1: The Effect of Force on Acceleration RP - Results
Create a table for your results. It will need to have at least the three columns shown
If your data logger does not calculate acceleration for you, you will need to include extra columns to the left of the acceleration column to show the measurements you are using to calculate the accelerations.
The force on the trolley is: mass (in kg) × g. Here, g is the Earth’s gravitational field strength, which has a value of 10 N/kg.
(The columns in the table should be: Mass on holder in kg, Force on trolley in N, and Acceleration in m/s^2, which can be tested 3 times with an average.)
(A similar table will be needed for Part 2.)
Then using this information, a graph can be drawn up, with Force (N) on the X-Axis and Average Acceleration (m/s^2) on the Y-Axis (this graph should give a linear positive correlation).
Part 2: The Effect of Mass on Acceleration - Equipment
The same as for Part 1, plus
- Several more trolleys to stack together with the first one
- Abalance to measure a trolley’s mass
The rest of the Equipment is:
- Trolley
- Piece of card shaped like this:
- Ruler (30 cm is long enough)
- Sticky tape or tack
- Pulley with clamp
- Mass holder and 50 g masses
- Wooden block, or lump of modelling clay (if needed to protect pulley)
- String or strong thread
- Data logger
- Light gate, with connecting lead
- Clamp stand and clamp for light gate
Part 2: The Effect of Mass on Acceleration - Method
Steps 1–4 of the method for Part 2 are the same as for Part 1. The apparatus is arranged in the same way as before, and you will use the light gate and data logger to measure accelerations as you did before.
The next steps are different, and are given below.
- Measure the length of each card segment, and make a note of this.
- Set up the apparatus as shown in the diagram below. When the trolley is as close to the pulley as it can get, the bottom of the mass holder should be between 0.5 cm and 1 cm above the floor.
- During this experiment the trolley will travel towards the pulley. If you need to, place a lump of modelling clay or a block in front of the pulley to protect it from being hit by the trolley.
- Set up the data logger. You will use its measurements to find the trolley’s acceleration. There are different ways of doing this, depending on the data logger and the method your teacher asks you to use.
- You will be changing the mass (by stacking extra trolleys under the first one) but keeping the applied force the same (by keeping the same number of masses on the mass holder). First, measure the mass of one trolley. (You can assume all trolleys have the same mass.)
- Carry out a preliminary investigation to find a suitable amount of mass to put onto the mass holder to accelerate the trolley(s).
- Each time you change the number of stacked trolleys, measure the acceleration. You may need to change the height of the light gate so that the card still passes through it.
- Record the acceleration and the total mass (which includes the trolleys, the mass holder, and the masses on the holder).
- If you have time, measure acceleration twice for each number of trolleys. Record both results in your table and calculate their mean average.
Part 2: The Effect of Mass on Acceleration - Results
Create a suitable table for your results. (Hint: it will be similar to your table for Part 1, but with a column for mass instead of force.)
(The columns in the table should be: Mass on holder in kg, Mass on trolley in N, and Acceleration in m/s^2)
Then from here, you can use the results to plot a graph of Acceleration (Y-Axis) against Mass (X-Axis)
(See Goodnotes for more info)
The All Important Equation to Prove Newton’s 2nd Law (Part 1)
F=m x a
Force = Mass x Acceleration, so
Force / Average Acceleration = Mass.
And that is how you find out and prove the Mass of an object
What is an Independant Variable
In Independant Variable is the variable that is altered during a scientific experiment.
What is a Dependant Variable
A Dependant Variable is the variable being tested or measured during a scientific experiment.
What is a Control Variable
A Control Variable is the variable that is kept the same during a scientific experiment.
