Physics: Post your doubts here!

[tania]

Link ?

Q37 bhi please

 

[Thought blocker]

Q37 bhi please

15)
Answer should be zero
Hadi Murtaza
ZaqZainab

19)
you need to find the power input... power = work done / time
work done = F x D or rather F here as Weight =mg = to find mass you use the formula density = mass/volume= 1000 x 340 = 340000... now converting it to weight x 9.8 = 3332000 ... Work done = 3332000 x distance (30 ) = 99960000
for power it has to be per second and youre given in the question per minute so you divide by 60s = 99960000/60 = 1666000 mnow thats the power in to find the power output you multiply bv the efficiency of the turbine generator = 1499400 = 1.5 MW

37)
-->After voltage passes through some resistance it will decrease
-->The higher the resistance the greater the decrease in voltage
-->So it will decrease less after passing through 2 ohm than when passing through 4 ohm

 

[ZaqZainab]

15)
Answer should be zero
Hadi Murtaza
ZaqZainab

19)
you need to find the power input... power = work done / time
work done = F x D or rather F here as Weight =mg = to find mass you use the formula density = mass/volume= 1000 x 340 = 340000... now converting it to weight x 9.8 = 3332000 ... Work done = 3332000 x distance (30 ) = 99960000
for power it has to be per second and youre given in the question per minute so you divide by 60s = 99960000/60 = 1666000 mnow thats the power in to find the power output you multiply bv the efficiency of the turbine generator = 1499400 = 1.5 MW

37)
-->After voltage passes through some resistance it will decrease
-->The higher the resistance the greater the decrease in voltage
-->So it will decrease less after passing through 2 ohm than when passing through 4 ohm

its B

 

[Thought blocker]

its B

Why?

 

[ZaqZainab]

Why?

(10*10^-2*2) =0.2for anti clockwise
and clockwise (40*10^-2*4) =1.6 for clockwise
1.6-0.2=1.4

 

[Hadi Murtaza]

Q37 bhi please

Take moments about pivot
Resultant moment = (-2 × 0.1) + (4 × 0.4)
Resultant moment = -0.2 + 1.6
Resultant moment = 1.4 Nm

 

[Thought blocker]

(10*10^-2*2) =0.2for anti clockwise
and clockwise (40*10^-2*4) =1.6 for clockwise
1.6-0.2=1.4

Make a new convo b/w us...

 

[ShreeyaBeatz]

http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_s07_qp_1.pdf
question 40!

 

[Thought blocker]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s07_qp_1.pdf
question 40!

for finding the acceleration with lowest speed you have to divide no of protons with atomic mass
A. H ... 1/1 = 1
B. He ... 2/4 = 0.5
C. Li ... 3/7 = 0.43
D. Be ... 4/9 = 0.44
C has the lowest speed so C would be the answer.

 

[Asad Moosvi]

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s10_qp_13.pdf

Question 35 please!

 

[ShreeyaBeatz]

http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_w07_qp_1.pdf
In question 20, why is the answer A isnt it the whole area of graph ie C ?

 

[Thought blocker]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w07_qp_1.pdf
In question 20, why is the answer A isnt it the whole area of graph ie C ?

We apply the formula :¬
1/2 * F * extension
so 1/2 * 25 * 0.2 = 2.5 J

 

[Wolfgangs]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s13_qp_12.pdf
q20 AND 23 PLEASE

 

[Thought blocker]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s13_qp_12.pdf
q20

https://www.xtremepapers.com/commun...st-your-doubts-here.9860/page-523#post-820191

 

[Thought blocker]

 

[ShreeyaBeatz]

We apply the formula :¬
1/2 * F * extension
so 1/2 * 25 * 0.2 = 2.5 J

isnt work done the whole area under graph?

 

[ratedr0014]

PLEASE HELP, MJ 2012, variant 13
qs:4,8,10,21,28,31,32,34
just 8qs please someone take the time to help me out and explain

 

[Thought blocker]

isnt work done the whole area under graph?

well it depends on extension

 

[Wolfgangs]

http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_w05_qp_1.pdf
Q3 and Q5 please

 

[Student12]

PLEASE HELP, MJ 2012, variant 13
qs:4,8,10,21,28,31,32,34
just 8qs please someone take the time to help me out and explain

Post the link of the question paper, it will be easier for others to answer.