Physics Practical/P33 Details and General Practical Tips

[angel92]

Update 2

In the terminal velocity question the smaller bead will take longer to reach the bottom because it is lighter!

but which 1 wil reach terminal velocity first????

 

[RidaYasin]

heyy can anybody tell me which ball will reach the terminal velocity first,the one wid small diameter or the one wid larger?

 

[uofoe]

And here i'm posting possible errors and method of improvements for the second experiment....


Error

1. small air bubbles are formed on the marble/spheres/(any balls being used) which hindered the motion of the ball
2. two sets of reading not enough to draw a valid conclusion
3. human error in timing
4. marble may have not reached terminal velocity


Method of improvements

1. release the ball/marble just a few mm above the oil surface
2. take more readings and plot a graph
3. use light gate to trigger stopwatch/high speed camera with known time intervals/use video camera with slow motion replay
4. ensure the terminal velocity by increasing the release height/using long tube/measure velocity at two intervals to check terminal velocity reached.

thnx guys...really...God bless u....

 

[s.hijazi]

there are two options
1- the one with the larger mass will fall more quickly so it will possibly not reach terminal velocity by then!! According to that, the one with the smaller diameter (less mass) will reach terminal velocity first
2-the one with the greater surface area perpendicular to the direction of fall (larger diameter) will reach terminal velocity first because it will experience most resisitance/drag force

 

[RidaYasin]

thanks alot @ s.hijazi!

 

[Aamir Khan]

can anyone here tell me the difference between and functions of a semiconductor diode and a light emitting diode? and are there any pointers for while setting up the circuit,,any thing we should be careful of?

 

[Uranium-238]

it is better to depend on theoretical results for viscosity..
if the bead is small provided its of same material
then equate the following......
weight=viscosity force where F=6"pi""meu"rv
weight=mass into volume
the overall equation shows that v is proportional to r2 which means its independent of mass..it only depends on density and radius
Interpretation: hence if the bead is small, then the radius is small and the velocity decreases so it takes much time to fall through a given distance!!!!
-----------------------------------------------------------------------------------------------------------------
Always believe on theory than on experimental results ...It really helps!!!

 

[MAVtKnmJ]

So how did it go guys? Give me the details of the paper.

 

[intel1993]

it was awsome dude.....luved it...

as duiscussed..
q1 was abt diode...
there was diode given and a 200 ohm fixed resitor and nan ammeter and a volmeter attached in parallel to diode...
the basic concept of the experimen was how the pd varies along diode and how current is affected....

so now its tyme t draw table..
we have to reduce the voltage ...its written...
have to take 6 readings...
colums included V , I and V*10(v with power 10..)

we have to made the graphy current on y xis.... n V*10 on x axis.....

and as usual have to find gradient and y inetrcept..
then an equation was given including constant a and b...

I=aV*10 + b..

a simple equation with simple answers...........

now its tyme for q2

cylinder was provided filled with oil..
marks were made on cylinder in which we have to do all the owrk..
balls wre given of different diameter ...1 was large size an other was small size..

first it asks...
distance between the marks.
then dia of small size ball...
tme taken by the ball in the specific distance marked...
then percentage uncertanity..
same was repeated for large ball..
then a realtion was given..

v=kd*2 (d= diameter)
we have to justify it....
after that a question on significant figures n than as usaula...
error and improvements...


so this was the full paper.......

 

[MAVtKnmJ]

Hahaha great, you guys will definitely score BIG in this paper!
Now it's our turn ;(
Please pray for our success as well!

 

[intel1993]

yeah Allah will help u too.....

 

[bilal_92]

guys p34 any details????

 

[MAVtKnmJ]

Check the other forums, they are just mostly speculations!

 

[kerry]

plz guys... provide some detail for p34...i looked at alot of threads but they only say its over oscillation with prism and magnet with threads...nothing like what was provided for paper 33...plzz this is the thing i am worried about the most....HELP

 

[MAVtKnmJ]

Well that information should be more than enough for you to prepare your exam If I do get any updates I will post a new thread!

 

[kerry]

thnks...but i have never done a physics lab and i am doing physics after 4 yrs...so its hard now...but i appreciate every effort done here...thanks to all of u!!!

 

[MAVtKnmJ]

That's strange, you should have joined an academy or hired a teacher with whom you should have done the practicals. It's all about practice and time management in practicals!

Anyways, good luck to you!