BOb148
Badges: 9
Rep:
?
#1
Report Thread starter 1 year ago
#1
The national grid supplied a house with 18,000,000 j of energy in 1 hour. What was the average current supplied to the house during that hour? ( 5 marks) thanks
0
reply
SmartMemoryGirl!
Badges: 13
Rep:
?
#2
Report 1 year ago
#2
(Original post by BOb148)
The national grid supplied a house with 18,000,000 j of energy in 1 hour. What was the average current supplied to the house during that hour? ( 5 marks) thanks
Q = E÷V
Charge flow = Energy ÷ Potential difference
Q=18,000,000 ÷ 230V
Q=78260.86956521738
I = Q÷t
Current = Charge ÷ time
Current = 78260.86956521739 ÷ 3600s
Current = 21.73913043478260 Amps
This sounds right because they use a low amp since to transfer a lot of energy you either use a high amp or voltage. Since a high amp dissipates a lot of thermal energy they use a low amp and high voltage. This was in the P1-4 test for combined science .
0
reply
Bulletzone
Badges: 22
Rep:
?
#3
Report 1 year ago
#3
Realised it's a gcse question.

Alternatively OP, You can say that Power = Energy transferred ÷ Time (In seconds)

then since you know Power = Voltage x Current
just divide the Power by 230V to get the value of Current.
1
reply
whyrevision
Badges: 1
Rep:
?
#4
Report 1 year ago
#4
(Original post by Bulletzone)
Realised it's a gcse question.

Alternatively OP, You can say that Power = Energy transferred ÷ Time (In seconds)

then since you know Power = Voltage x Current
just divide the Power by 230V to get the value of Current.
Where did you get the 230V from?
0
reply
Bulletzone
Badges: 22
Rep:
?
#5
Report 1 year ago
#5
(Original post by whyrevision)
Where did you get the 230V from?
230 Volts is the standard UK potential difference of an Electrical A.C socket.
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

  • SOAS University of London
    Development Studies, Interdisciplinary Studies, Anthropology and Sociology, Languages, Cultures and Linguistics, Arts, Economics, Law, History, Religions and Philosophies, Politics and International Studies, Finance and Management, East Asian Languages & Cultures Postgraduate
    Sat, 25 Jan '20
  • University of Huddersfield
    Undergraduate Open Day Undergraduate
    Sat, 25 Jan '20
  • The University of Law
    Solicitor Series: Assessing Trainee Skills – LPC, GDL and MA Law - Guildford campus Postgraduate
    Wed, 29 Jan '20

How many uni open days have you been to/did you go to?

0 (64)
27%
1 (39)
16.46%
2 (40)
16.88%
3 (32)
13.5%
4 (16)
6.75%
5 (20)
8.44%
6 (6)
2.53%
7+ (20)
8.44%

Watched Threads

View All
Latest
My Feed