« previous next »
Pages: 1 ... 15 16 [17] 18 19 ... 25   Go Down

Author Topic: Maths & Physics Help  (Read 61005 times)

Offline Christy

  • SF Citizen
  • ***
  • Posts: 145
  • Reputation: 2
Re: Maths & Physics Help
« Reply #240 on: May 09, 2009, 07:46:13 pm »
Quote from: hyebyekadal on May 09, 2009, 07:40:22 pm
Hey guys I did this MCQ paper and I got everything EXCEPT this question.  I really don't understand why the answer is C. I thought the answer was D. Thanks in advance!
P.S. I have attacehd this particular question if you haven't noticed yet!

i think its C just a guess and a hunch :P
Logged

Offline hyebyekadal

  • SF Citizen
  • ***
  • Posts: 182
  • Reputation: 17
Re: Maths & Physics Help
« Reply #241 on: May 09, 2009, 08:11:18 pm »
I kow that already though i want to know why!
Logged

Offline Zain-Xa

  • SF Overlord
  • *********
  • Posts: 11833
  • Reputation: 10822
  • I got an "I <3 ?" written at the back of my hand
Re: Maths & Physics Help
« Reply #242 on: May 09, 2009, 08:11:52 pm »
Maths:
Q) Sarah has a set of holiday photographs (fewer than hundred) which she is going to put into a photograph album.
If she puts 2 photgraphs on each page, she will have 1 photograh left over.
If she puts 3 photgraphs on each page, she will have 2 photograh left over.
If she puts 4 photgraphs on each page, she will have 3 photograh left over.
If she puts 5 photgraphs on each page, she will have 4 photograh left over.
How many photgraphs does she have altogether?

plz help ASAP !!
Thanks in adv.  ;D
Logged
What can I do, to make it right
Falling so hard so fast this time
What did I say, what did you do?
How did I fall in love with you?


zzzzzZZZZZZzzzzzzzzz

I'll be strong.. I'll be wrong.. all the love goes on.. Oh im just a girl tryna find a place in this worLD..  Taylor swift <3

Offline hyebyekadal

  • SF Citizen
  • ***
  • Posts: 182
  • Reputation: 17
Re: Maths & Physics Help
« Reply #243 on: May 09, 2009, 08:27:13 pm »
Guys one more question !!!
Q 36 in the attached paper why is the correct answer D? Shouldn't it be C? When the resistance increases whys does the p.d. increase?
Again thanks in advance!!
Logged

Offline hyebyekadal

  • SF Citizen
  • ***
  • Posts: 182
  • Reputation: 17
Re: Maths & Physics Help
« Reply #244 on: May 09, 2009, 08:28:31 pm »
Guys one more question !!!
Q 36 in the attached paper why is the correct answer D? Shouldn't it be C? When the resistance increases whys does the p.d. increase?
Again thanks in advance!!


Opps! Forgot to upload paper! Here!
Logged

Offline hyebyekadal

  • SF Citizen
  • ***
  • Posts: 182
  • Reputation: 17
Re: Maths & Physics Help
« Reply #245 on: May 09, 2009, 08:32:03 pm »
Zainy the answer is 59!
Logged

Offline Zain-Xa

  • SF Overlord
  • *********
  • Posts: 11833
  • Reputation: 10822
  • I got an "I <3 ?" written at the back of my hand
Re: Maths & Physics Help
« Reply #246 on: May 09, 2009, 08:49:33 pm »
could u plz show me how u got the answer ???  ???
Logged
What can I do, to make it right
Falling so hard so fast this time
What did I say, what did you do?
How did I fall in love with you?


zzzzzZZZZZZzzzzzzzzz

I'll be strong.. I'll be wrong.. all the love goes on.. Oh im just a girl tryna find a place in this worLD..  Taylor swift <3

Offline astarmathsandphysics

  • SF Overlord
  • *********
  • Posts: 11271
  • Reputation: 65534
  • Gender: Male
  • Free the exam papers!
Re: Maths & Physics Help
« Reply #247 on: May 09, 2009, 09:05:37 pm »
Quote from: zainy on May 09, 2009, 08:11:52 pm
Maths:
Q) Sarah has a set of holiday photographs (fewer than hundred) which she is going to put into a photograph album.
If she puts 2 photgraphs on each page, she will have 1 photograh left over.
If she puts 3 photgraphs on each page, she will have 2 photograh left over.
If she puts 4 photgraphs on each page, she will have 3 photograh left over.
If she puts 5 photgraphs on each page, she will have 4 photograh left over.
How many photgraphs does she have altogether?

plz help ASAP !!
Thanks in adv.  ;D
From 1st condition ther number is odd andfrom las condition the last digit is 4 or 9 so must be nine sin the number is odd, so it must be 9,19,29,39,49,59,69,79,89,99. It has remainder 2 when dibided be 3 and remainder 3 when divided by 4.

The answer is 59
Logged

Offline godfather93

  • SF Senior Citizen
  • *****
  • Posts: 720
  • Reputation: 799
  • Gender: Male
  • Tomorrow is a day that changes everyday
Re: Maths & Physics Help
« Reply #248 on: May 09, 2009, 09:12:47 pm »
when the resistance increases, the voltage across it increases because it is consuming more of the power that is being supplied by the battery.
Logged

Offline hyebyekadal

  • SF Citizen
  • ***
  • Posts: 182
  • Reputation: 17
Re: Maths & Physics Help
« Reply #249 on: May 09, 2009, 09:13:23 pm »
astar could you please answer my question?? THanks!
Logged

Offline hyebyekadal

  • SF Citizen
  • ***
  • Posts: 182
  • Reputation: 17
Re: Maths & Physics Help
« Reply #250 on: May 09, 2009, 09:13:57 pm »
Now I am lost....
Logged

Offline Zain-Xa

  • SF Overlord
  • *********
  • Posts: 11833
  • Reputation: 10822
  • I got an "I <3 ?" written at the back of my hand
Re: Maths & Physics Help
« Reply #251 on: May 09, 2009, 09:17:35 pm »
i got the first part by i dont get wt u divide by 2 to get the remainder 3... etc.  ???
Logged
What can I do, to make it right
Falling so hard so fast this time
What did I say, what did you do?
How did I fall in love with you?


zzzzzZZZZZZzzzzzzzzz

I'll be strong.. I'll be wrong.. all the love goes on.. Oh im just a girl tryna find a place in this worLD..  Taylor swift <3

Offline godfather93

  • SF Senior Citizen
  • *****
  • Posts: 720
  • Reputation: 799
  • Gender: Male
  • Tomorrow is a day that changes everyday
Re: Maths & Physics Help
« Reply #252 on: May 09, 2009, 09:20:18 pm »
example - suppose a bulb is connected to a power source. Nothing else except for the bulb and the connecting wires to the power supply. Now let us add a resistor into the circuit (in series). you will notice the bulb gets dimmer. Why is it? Its because the resistor is using up some of the battery's voltage, thus, decreasing the voltage supplied to the bulb (you probably know that a bulb's brightness decreases whe the voltage decreases). Now, instead of the resistor, add a variable resistor. As you increase the resistance, the bulb gets dimmer. More voltage is being used up by the variable resistor and less of the voltage from the battery is reaching the bulb.
Hopefully you get it now.
Logged

Offline astarmathsandphysics

  • SF Overlord
  • *********
  • Posts: 11271
  • Reputation: 65534
  • Gender: Male
  • Free the exam papers!
Re: Maths & Physics Help
« Reply #253 on: May 09, 2009, 09:20:44 pm »
Quote from: hyebyekadal on May 09, 2009, 08:28:31 pm
Guys one more question !!!
Q 36 in the attached paper why is the correct answer D? Shouldn't it be C? When the resistance increases whys does the p.d. increase?
Again thanks in advance!!


Opps! Forgot to upload paper! Here!

The answer is D We have a potential divider. The LDR is a semiconductor and the resistance goes up in the dark because less electrons move into the conduction band. VLDR=VRLDR/(R+RLDR) and VLDR increases with |RLDR
Logged

Offline Zain-Xa

  • SF Overlord
  • *********
  • Posts: 11833
  • Reputation: 10822
  • I got an "I <3 ?" written at the back of my hand
Re: Maths & Physics Help
« Reply #254 on: May 09, 2009, 09:24:40 pm »
plllzz answer my question   :'(
Logged
What can I do, to make it right
Falling so hard so fast this time
What did I say, what did you do?
How did I fall in love with you?


zzzzzZZZZZZzzzzzzzzz

I'll be strong.. I'll be wrong.. all the love goes on.. Oh im just a girl tryna find a place in this worLD..  Taylor swift <3
Pages: 1 ... 15 16 [17] 18 19 ... 25   Go Up
« previous next »