average_human
Badges: 5
Rep:
?
#1
Report Thread starter 2 weeks ago
#1
I am not sure how to do this question.
Attached files
Last edited by average_human; 2 weeks ago
0
reply
seabasssss
Badges: 6
Rep:
?
#2
Report 2 weeks ago
#2
Part A:
Is a series circuit so voltage will be shared between components according to there resistance. Ratio of 5:1 therefore the LDR will take 5/6 of the total voltage = 5V
0
reply
average_human
Badges: 5
Rep:
?
#3
Report Thread starter 2 weeks ago
#3
(Original post by seabasssss)
Part A:
Is a series circuit so voltage will be shared between components according to there resistance. Ratio of 5:1 therefore the LDR will take 5/6 of the total voltage = 5V
Thank you! Do you know how to work out parts b and c
0
reply
seabasssss
Badges: 6
Rep:
?
#4
Report 2 weeks ago
#4
You got b correct
0
reply
seabasssss
Badges: 6
Rep:
?
#5
Report 2 weeks ago
#5
For part C, i think the answer would be 0 because with no resistance the LDR isn't taking any share of the voltage so it is effectively not there.
Hope this helps but i'm not completely certain!
0
reply
Joinedup
Badges: 20
Rep:
?
#6
Report 2 weeks ago
#6
(Original post by seabasssss)
For part C, i think the answer would be 0 because with no resistance the LDR isn't taking any share of the voltage so it is effectively not there.
Hope this helps but i'm not completely certain!
:yep: :top:
0
reply
Sophhhowa
Badges: 15
Rep:
?
#7
Report 2 weeks ago
#7
LDR goes from 500ohms when dark to 0 when bright. 100 ohm one doesn’t change. Series so RT= sum of resistances. V=IR so when dark I = V/(100+500) and when bright I=V/100 I think fixed resistor was 100ohms if not replace its resistance into equation. As light intensity increases current increases and resistance decreases. Need anymore help, just ask
0
reply
Sophhhowa
Badges: 15
Rep:
?
#8
Report 2 weeks ago
#8
Also V across each component = IR where R is resistance of that component so when bright LDR takes no voltage as R=0ish
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

University open days

  • De Montfort University
    Undergraduate Open Day Undergraduate
    Sat, 7 Dec '19
  • Buckinghamshire New University
    Undergraduate Undergraduate
    Sat, 7 Dec '19
  • Regent's University London
    Undergraduate Open Day Undergraduate
    Sat, 7 Dec '19

Which party will you be voting for in the General Election?

Conservatives (68)
19.32%
Labour (171)
48.58%
Liberal Democrats (49)
13.92%
Green Party (21)
5.97%
Brexit Party (4)
1.14%
Independent Group for Change (Change UK) (3)
0.85%
SNP (8)
2.27%
Plaid Cymru (3)
0.85%
Democratic Unionist Party (DUP) (0)
0%
Sinn Fein (5)
1.42%
SDLP (0)
0%
Ulster Unionist (2)
0.57%
UKIP (6)
1.7%
Other (1)
0.28%
None (11)
3.13%

Watched Threads

View All