AS Physics Prac Query

[$!$RatJumper$!$]

Hey guys. How did it go for you.

Just a few questions:

1) What were the two experiments you guys had to do?
2) Were there any tricky/hard/confusing questions in it? (If so, what did you have to do)
3) Was the paper similar to any past paper before?
4) Was there any confusing error/limitations for the last question?

[Deadly_king]

Hey guys. How did it go for you.

Just a few questions:

1) What were the two experiments you guys had to do?
2) Were there any tricky/hard/confusing questions in it? (If so, what did you have to do)
3) Was the paper similar to any past paper before?
4) Was there any confusing error/limitations for the last question?

You sat for it on Tuesday, right?

I'll be having my practical next thursday, so I can't really help. But I heard from some friends that it was pretty much easy

[$!$RatJumper$!$]

oh no i havent dont it bro i was askin how it went so i could be better prepared lol

[Deadly_king]

oh no i havent dont it bro i was askin how it went so i could be better prepared lol

Ooh.....confusion buddy....my bad

I had a look at their practicals today. It was quite easy.

The first number was about a metre rule held in equilibrium on a round large tube. Then you need to add pins and each time measure the height from the ground to the almost horizontal metre rule; h1 from the right side and h2 from the left side. Then you need to plot a graph and find gradient and y-intercept.

Second was about water leaking from a hole in a bottle. You should measure the time taken it took for the water to move from a line to another one.

I believe we'll be getting same principle

[$!$RatJumper$!$]

Ooh.....confusion buddy....my bad

I had a look at their practicals today. It was quite easy.

The first number was about a metre rule held in equilibrium on a round large tube. Then you need to add pins and each time measure the height from the ground to the almost horizontal metre rule; h1 from the right side and h2 from the left side. Then you need to plot a graph and find gradient and y-intercept.

Second was about water leaking from a hole in a bottle. You should measure the time taken it took for the water to move from a line to another one.

I believe we'll be getting same principle

Thats nice to hear it was easy

umm jus a question, what were the errors and improvements for that prac?

[Deadly_king]

Thats nice to hear it was easy

umm jus a question, what were the errors and improvements for that prac?

These were pretty much easy :

Errors
1. Two sets of readings were not enough to draw a valid conclusion.
2. The amount of water which is to be leaked out was small and hence rapid such that it was difficult to judge when the water has passed the line.
3. The bottle was not horizontal and each time we set the bottle it was not inclined at the same angle.
4. Water is a colourless liquid such that it does not have a good contrast.

Improvements :
1. Take more readings and plot a suitable graph as a means of averaging.
2. Use a larger bottle such that it takes more time, hence reducing % uncertainty in the measurement of time.
3. Make use of a spirit level to keep the bottle horizontal.
4. Make use of a dyed solution which will have a better contrast such that values can be taken more accurately.

[$!$RatJumper$!$]

These were pretty much easy :

Errors
1. Two sets of readings were not enough to draw a valid conclusion.
2. The amount of water which is to be leaked out was small and hence rapid such that it was difficult to judge when the water has passed the line.
3. The bottle was not horizontal and each time we set the bottle it was not inclined at the same angle.
4. Water is a colourless liquid such that it does not have a good contrast.

Improvements :
1. Take more readings and plot a suitable graph as a means of averaging.
2. Use a larger bottle such that it takes more time, hence reducing % uncertainty in the measurement of time.
3. Make use of a spirit level to keep the bottle horizontal.
4. Make use of a dyed solution which will have a better contrast such that values can be taken more accurately.

Cool thank for that..
so no parallax error at all in this experiment?

[Deadly_king]

Cool thank for that..
so no parallax error at all in this experiment?

Ooh.........you can add parallax as well in measuring the diameter of the bottle though you were given two sets square to prevent that.

I was told by a teacher to try be unique and use parallax only in emergency

[$!$RatJumper$!$]

I see.. ok so what types of experiments would you use parallax? I get confused because in experiments where its VERY evident parallax was involved, the mark scheme says ignore parallax lol Are there only certain conditions when you can use it bro?

[Deadly_king]

I see.. ok so what types of experiments would you use parallax? I get confused because in experiments where its VERY evident parallax was involved, the mark scheme says ignore parallax lol Are there only certain conditions when you can use it bro?

I think for estimates, they don't accept parallax since there are pretty much more errors occuring.

So use parallax when you are accurately measuring something, like the length of a thread or something like that.

But like I mentioned earlier, avoid stating parallax as long as you can. Try to find new but sure sources of errors

[Dania]

Each experiment has different errors & uncertainties for example in electricity questions while measuring resistance, we do not consider lead contact resistance, so that's an error too

[Deadly_king]

Each experiment has different errors & uncertainties for example in electricity questions while measuring resistance, we do not consider lead contact resistance, so that's an error too

You're indeed right

We can also talk about the uncertainty in the measuring instruments used such as voltmeter or ammeter.

[$!$RatJumper$!$]

Wat is lead contact resistance?

[Deadly_king]

Wat is lead contact resistance?

Ooh.......it is the contacts that you use to join the different electrical components together. They are usually found at the end of each connecting wires.

It's something like that though am pretty sure you'll be getting one much older and uglier than this one for your practicals

[$!$RatJumper$!$]

haha ok yeah i know what u mean now