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Science Help (1 Viewer)
- Thread starter livsta
- Start date
So consider this experiment as like an example:
So we want to determine the amount of dissolved carbon dioxide in a coke can
Our method to do so would be to heat up the coke can which will cause the carbon dioxide to leave the coke
So then what we can do is if we measure the amount of mass of the can before and the mass of the can after heating that will tell us how much carbon dioxide was there
So lets say we did the experiment for a Pepsi can as well so we can compare the two in terms of how much carbon dioxide they have
Then the controlled variables in the experiment are the things we keep constant and don't change between experimental runs. This allows for a fair test. Like think of it like this if you used 250 mL of coke and 100 mL of Pepsi you can't compare the two because they would have different amount of carbon dioxide just even from the volumes
So what the controlled variables would be in your experiment would be things like the amount of the drinks used, the temperature of heating, time heated for etc.
The control is very different from this. It's basically something in experiments you use as a way to improve the accuracy or validity of your result.
So think about what else would happen if we heated up our coke can. Heating would also cause some of the water in the coke to evaporate and therefore the mass change we found wouldn't be all due to carbon dioxide leaving, some of it will be due to the water being evaporated as well
So a control for that experiment would be to heat an equal amount of water at the same temperature and same amount of time, and then you measure how much water evaporated so we would be able to account for how much of the mass losses in our coke can experiment was due to water evaporating
This means we will get a more accurate number for how much carbon dioxide was in the coke
So summarising:
controlled variables - factors of an experiment kept constant throughout different trials
Control - something used to account for a problem with the experimental design or to improve the accuracy or validity of the result
So we want to determine the amount of dissolved carbon dioxide in a coke can
Our method to do so would be to heat up the coke can which will cause the carbon dioxide to leave the coke
So then what we can do is if we measure the amount of mass of the can before and the mass of the can after heating that will tell us how much carbon dioxide was there
So lets say we did the experiment for a Pepsi can as well so we can compare the two in terms of how much carbon dioxide they have
Then the controlled variables in the experiment are the things we keep constant and don't change between experimental runs. This allows for a fair test. Like think of it like this if you used 250 mL of coke and 100 mL of Pepsi you can't compare the two because they would have different amount of carbon dioxide just even from the volumes
So what the controlled variables would be in your experiment would be things like the amount of the drinks used, the temperature of heating, time heated for etc.
The control is very different from this. It's basically something in experiments you use as a way to improve the accuracy or validity of your result.
So think about what else would happen if we heated up our coke can. Heating would also cause some of the water in the coke to evaporate and therefore the mass change we found wouldn't be all due to carbon dioxide leaving, some of it will be due to the water being evaporated as well
So a control for that experiment would be to heat an equal amount of water at the same temperature and same amount of time, and then you measure how much water evaporated so we would be able to account for how much of the mass losses in our coke can experiment was due to water evaporating
This means we will get a more accurate number for how much carbon dioxide was in the coke
So summarising:
controlled variables - factors of an experiment kept constant throughout different trials
Control - something used to account for a problem with the experimental design or to improve the accuracy or validity of the result
okay thankyou.
so if i was doing an experiment on how heart rate changes due to to different physical activities being performed, im guessing the controlled variable would be the amount of time performing the physical activty, and the same person conducting each activty. However what would the control be?
so if i was doing an experiment on how heart rate changes due to to different physical activities being performed, im guessing the controlled variable would be the amount of time performing the physical activty, and the same person conducting each activty. However what would the control be?
Control is something you can compare to. So the control in your case would be the heart rate when the person is doing nothing