how was the physics atp 5054/42 may/june 2014

[Dark Destination]

only 1 thing I,ll tell u:Stop with the lang abuse;Probably I wont,but a good chance is others wud report or anything.
Dunno if u find this whole idea of abusing amusing or not(or offending or likewise).So u might want to consider tht and PIPE DOWN.
one more thing,u still haven,t proved anything I stated wrong.like I said buoyancy even though difficult was only illustrated in the question.It was at a really crude or basic level and questions were not even asked explicitly or implicitly abt tht.So there u go!

What was the answer to question 1 b? Many people wrote many different answers. .-.

 

[muhammadali233]

Just trying to stop this meaningless argument, and it's 25%.

whatever you say sire

 

[Abdul Hanan]

When they asked for advantage of DIGITAL AMMETER, i said it gives a more accurate reading as parallax error is avoided. Is this correct? :3

yea correct!

 

[muhammadali233]

dense objects are heavy.......e.g metals etc

was it wood or glass?

 

[Dark Destination]

For question 1 a, i wrote that the rod keeps moving and it is difficult to align the ruler with the rod to take the reading. That is why it cannot be measured accurately.

But then in part b, they asked for a way to measure it accurately.
And i wrote immerse a rule into the water, and make sure its zero mark co-incides with the water level. Then use a set-square to take the reading L of the rod about the water. Make sure to look perpendicularly to avoid parallax error.

 

[Abdul Hanan]

was it wood or glass?

glass i think but not sure......

 

[M.Omar]

What was the answer to question 1 b? Many people wrote many different answers. .-.

yeah diff I know
though the most suitable in my viewing and regarding wht is said in MS AND also in phy lab practicals
It wud be:
1.Removing parallax by vertically aligning rule with set sq and also for reading the value from the rule.\2.this leads to 2nd point which is to hold rule with clamp but more imp holding wooden rod once it becomes steady in water with a clamp,by being very meticulous and slowly closing the jaws.Doing this will also not cause disturbance when measuring.If u r thinkg of the fact tht the rod will budge,then think of this:The jaws slowly close,rod is steady,firstly small force is exerted,not causing ruler to buge and can subsequently be tightended
3.Marking correct water level by meniscus and all tht.
This I think is the typical answer asked and also required based on Previous qp and ms and lab practices

 

[Abdul Hanan]

was it wood or glass?

bro my teacher just said that a graph starting from zero will not make sense

 

[M.Omar]

For question 1 a, i wrote that the rod keeps moving and it is difficult to align the ruler with the rod to take the reading. That is why it cannot be measured accurately.

But then in part b, they asked for a way to measure it accurately.
And i wrote immerse a rule into the water, and make sure its zero mark co-incides with the water level. Then use a set-square to take the reading L of the rod about the water. Make sure to look perpendicularly to avoid parallax error.

But placing ruler wud cause water disturbance and rod will wobble.I believe thts the reason they asked question part a and how we cud thus rectify tht in part b.Hence I also thought of using clamps to be mainspring of answer

 

[Dark Destination]

But placing ruler wud cause water disturbance and rod will wobble.I believe thts the reason they asked question part a and how we cud thus rectify tht in part b.Hence I also thought of using clamps to be mainspring of answer

In part a they said how can it not be accurately measured, so i said that it would be difficult to align rule and match the exact reading.

Then in part b, it would be logical to TELL A WAY to get the accurate reading, that is tell a way to avoid parallax error. That can be done by using SET-SQUARE or something.

But people wrote a whole experiment for this part. Some wrote take out the rod from the water, and measure the part that is not wet.
Some marked the water level, and measured it, and something like that.
Some, FROZE the water, and measured the length L easily.
Some, Measured from botton of beaker to TOP, and then water level, and subtracted.

There are a wide range of answers, how will they mark such questions?

Did we have to tell a new experiment?
Why can't we use a rule?
I'm only inserting the bottom space below the zero mark, that's like a few millimeters, that won't cause much disturbance.
And plus, no method can perfectly measure Length L.

 

[muhammadali233]

glass is denser than water okay?are u okay with that?
So starting from zero means that when there was no rubberband it was fully submerged simple why are you guys not understanding this ''bogus'' Concept

 

[muhammadali233]

bro my teacher just said that a graph starting from zero will not make sense

http://wiki.answers.com/Q/Is_glass_denser_than_water
if glass is dense so it will obviously sink!

 

[Abdul Hanan]

glass is denser than water okay?are u okay with that?
So starting from zero means that when there was no rubberband it was fully submerged simple why are you guys not understanding this ''bogus'' Concept

without rubber band (no additional weight) it was full in?? with extra weight (rubber bands) it started to float?
maybe it was not glass then........
but it was a vertical rod floatin with rubber bands(extra weight) so it will for sure float without rubberbands (no additional weight) giving value without rubber bands not zero but someway above the 8.6........

 

[muhammadali233]

without rubber band (no additional weight) it was full in?? with extra weight (rubber bands) it started to float?
maybe it was not glass then........
but it was a vertical rod floatin with rubber bands(extra weight) so it will for sure float without rubberbands (no additional weight) giving value without rubber bands not zero but someway above the 8.6........

metal sink in water,you agree on that ?but ships dont why?
same here ,just because rubberband has made it less dense and all buoyancy stuff is happenin there

 

[muhammadali233]

without rubber band (no additional weight) it was full in?? with extra weight (rubber bands) it started to float?
maybe it was not glass then........
but it was a vertical rod floatin with rubber bands(extra weight) so it will for sure float without rubberbands (no additional weight) giving value without rubber bands not zero but someway above the 8.6........

Have a practial mind and dont be laqeer ka faqeer

 

[Abdul Hanan]

metal sink in water,you agree on that ?but ships dont why?
same here ,just because rubberband has made it less dense and all buoyancy stuff is happenin there

how can rubber bands make it less dense when they add to the weight... which makes the rod go down and "l" lower

 

[Abdul Hanan]

Have a practial mind and dont be laqeer ka faqeer

in addition density is mass per unit volume i.e amount of matter per unit volume.by adding rubber bands, amount of matter is increased so the rod will float with higher portion out when less matter on it (so "l" will be most when no rubber band on rod as matter is least and density lowest ,without rubberbands)

 

[muhammadali233]

how can rubber bands make it less dense when they add to the weight... which makes the rod go down and "l" lower

just tell me why boats dont sink

 

[Abdul Hanan]

just tell me why boats dont sink

due to air in boat it is less dense than water so it floats..............
but here rubberbands are not air they are extra weight.
tell me did adding extra rubber bands decreased value of "l"? yes it did. decreasing rubber bands increases value of l. so if rubber band "0" then "l" is greatest...
"l" can never be zero with 0 rubber bands.... "l" is only 0 with 11 rubber bands...................

 

[haris jutt]

oh it goes something like that
View attachment 41522

this graph make no sense to.
Try to read this graph ?
? We are getting 6cm height by Attaching 1 rubber band (according to your graph) and we will be getting same height by attaching 4 rubber bands is it possible?