Physics: Post your doubts here!

[Abdulrab]

where ??? no link !!

 

[rz123]

oh man... here it is check these 2 : http://miniphysics.blogspot.com/2010/11 ... h1-h2.html

http://studyguide.pk/?page_id=233

 

[smartangel]

Please explain November 2010 PAPER 4 Q3 part i. why is it 8 and not 4?

 

[Abdulrab]

because 4 * 2 = 8

 

[Abdulrab]

http://www.xtremepapers.com/CIE/Interna ... _qp_13.pdf guys kindly solve these questions with full explanation thankss Q 11,14,17,22,31 and 35 thankks

 

[abcde]

http://www.xtremepapers.com/CIE/International%20A%20And%20AS%20Level/9702%20-%20Physics/9702_w10_qp_13.pdf guys kindly solve these questions with full explanation thankss Q 11,14,17,22,31 and 35 thankks

11. Acceleration due to free fall causes the vertical component of the velocity to increase until it reaches a constant value (when acceleration due to free fall equals air resistance). The horizontal component would obviously decrease to zero. Hence, B is correct.
14. Resultant moment = Sum of clockwise moments - Sum of anticlockwise moments
= (15 x 3) - ( 5 x 2 + 10 x 2) = 45 - 30 = 15 Nm.
Hence, A is correct.
22. None of the statements are correct (D). Solids are rigid because it's particles are held in fixed positions, not because they vibrate. Liquids flow because it's molecules are able to move by sliding over each other, not because they are closer than in a gas. Gases are less dense than liquids because its particles are further apart (occupy more volume) and not because the molecules in a gas move randomly. (Although the 2 statements are correct in their own right, they cannot be linked as proof of the validity of the other statement.)

 

[Abdulrab]

sir in Q 14 how hav u included 5 * 2 in the clockwise moment as the distance between the pivot and 5N FORCE IS 1 m !!! ??

 

[Abdulrab]

sorry yaar i got it !!! there was a little misunderstanding overaLL thanks

 

[Abdulrab]

what about 31 and 35 ????

 

[unique840]

what about 31 and 35 ????

35) the ques is abt the total voltage across the voltmeter, not abt the voltage across P or Q. the voltmeter is connected across the whole circuit so the total emf of the cell is measured by the voltmeter i.e. 4 V, irrespective of the point of the potentiometer.

 

[unique840]

V = IR
RESISTANCE per meter=0.0050
resistance of 800 m = 0.0050 * 800
resistance of 2 wires of 800 m = 0.0050 * 800 * 2
V of cable = (0.0050 * 800 * 2) * (0.60)
total voltage of cable and relay = 16 + voltage of cable
= 20.8 V

 

[babycry]

November 2004 question 18

18 A constant force of 9.0 kN, parallel to an inclined plane, moves a body of weight 20 kN through a distance of 40 m along the plane at constant speed. The body gains 12 m in height, as shown.
How much of the work done is dissipated as heat?
A 120kJ B 240kJ C 360kJ D 600kJ

thanks

 

[ambitious1]

Can someone please help me with uncertainty rules for paper 5?? for e.g. paper m/j 2008 Q2b

 

[markskoop]

A cricket ball is thrown vertically upward with a speed of 15.0 meters per second. What is the velocity of the cricket ball when it passes through a point 8.0 meters above the cricketer's hands?
Please help me this one...as soon as possible!!!!!!

 

[rz123]

^ lets find the time first when it has travelled 8 m.
so suvat equation applied : 8 = 15t + 1/2 multiply by -10 multiply by t ^2 ( ball decelerating so g= -10)

8 = 15t - 5t^2

5t^2 - 15t + 8 = 0 solve the equation and u will get time = 2.3 seconds

put this time in this equation v^2 - u^2 = 2as solve it u will get 8 m/s speed

P.S i dnt know my ans is right or wrong so u must write answer with the question as well so dat the answerer can confirm before posting the solution

 

[XPFMember]

Assalamoalaikum!


Physics Practical Tips - by arlery added...in the first post of this thread!

 

[Swoorup]

Hey I am new here, but I have been watching this forum as a guest from the past month.
Anyway to all those who are giving physics practical Paper 3 tomorrow here is some helpful guide.

Really helpful and covers every detail you need:

http://www.mediafire.com/?3venomdf078yj0f

Also I would like to say that be well prepared.

 

[babycry]

Please help me with the question which i uploaded.

 

[rz123]

^no file attached. is this is the same question which u posted 6 posts above?

 

[babycry]

yes it is the same question..pls help me.. anyone