IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => IGCSE/ GCSE => Sciences => Topic started by: superduper2009 on May 16, 2010, 10:58:42 pm

Title: Physics cie past paper question
Post by: superduper2009 on May 16, 2010, 10:58:42 pm

How do you solve Q 25, CIE physics, 2007 october november paper 1 (MCQ) and similar questions...
what is the formula used...
also on the same paper how do u do Q 20
Thanks in advance :D
superduper2009

Title: Re: Physics cie past paper question
Post by: Aodian on May 17, 2010, 05:20:30 pm

Cant help with Q25 but I can shed some light on Q20.

As we know the graph is usually drawn with Force on the Y-axis and extension or in this case Length on the X-axis.

What they've done for Q20 is switched the axis around. To find the strain energy you have to calculate the area under the graph. Since the axis is flipped, you'll need to calculate 1/2 X 0.20 X 25 = 2.5J
Hope that helped

Title: Re: Physics cie past paper question
Post by: ifraha18 on May 17, 2010, 05:50:16 pm

nov 2007..25

dsin thetha=n lambda
d sin45=3lambda
d=3lambda/sin45
d=3root2 lambda
the maximum value of sinetheha is 1
so fr highest order...nlamda/d<=sinthetha
                            nlamda/3root2lambda <=1
                            n/3root2<=1
                            n<=3root2
                            n<=4.24


so highest order is 4