Class 12 Exam > Class 12 Questions > If the length of the filament of a heater is ...
Start Learning for Free
If the length of the filament of a heater is reduced by 10% the power of the heater will
- a)increase by about 11%
- b)increase by about 19%
- c)decrease by about 29%
- d)Increase by about 9%
Correct answer is option 'A'. Can you explain this answer?
| FREE This question is part of | Download PDF Attempt this Test |
Verified Answer
If the length of the filament of a heater is reduced by10%the power of...
we know that P=V^2/R
=V^2/ρl/A
P'=1/(l-10/100l)
P'/P=l/(l-l/10)=10/9
P'-P/P*100=10/9*100
=11%
SO it increases by 11%
Most Upvoted Answer
If the length of the filament of a heater is reduced by10%the power of...
Power P=RV2
If length reduced 10% then new resistance of filament will be R′.
R′=0.9R
Now new power of heater is P2
P2=R′V2=0.9RV2=1.1P
% increase power=11%
If length reduced 10% then new resistance of filament will be R′.
R′=0.9R
Now new power of heater is P2
P2=R′V2=0.9RV2=1.1P
% increase power=11%
Free Test
FREE
| Start Free Test |
Community Answer
If the length of the filament of a heater is reduced by10%the power of...
**Given Information:**
- The length of the filament of a heater is reduced by 10%.
**To Find:**
- The percentage change in the power of the heater.
**Solution:**
Let's assume the initial length of the filament is L and the initial power of the heater is P.
**Step 1: Calculate the new length of the filament after reducing it by 10%:**
The length of the filament after reducing it by 10% can be calculated as:
New Length = L - (10/100)L = L - 0.1L = 0.9L
**Step 2: Calculate the new power of the heater:**
We know that the power of a heater is directly proportional to the square of its length.
Therefore, the new power can be calculated as:
New Power = (New Length)^2 = (0.9L)^2 = 0.81L^2
**Step 3: Calculate the percentage change in power:**
The percentage change in power can be calculated using the formula:
Percentage Change = (New Power - Initial Power) / Initial Power * 100
Substituting the values, we get:
Percentage Change = (0.81L^2 - P) / P * 100
**Step 4: Simplify the expression:**
To compare the percentage change with the given options, we need to simplify the expression.
Let's assume the initial length L = 1 for simplicity.
Initial Power = P = L^2 = 1^2 = 1
Substituting the values, we get:
Percentage Change = (0.81 - 1) / 1 * 100 = -19%
Since the percentage change is negative (-19%), this means that the power of the heater has decreased by 19% when the length of the filament is reduced by 10%.
Therefore, none of the given options (a), (b), (c), or (d) are correct.
Please recheck the question and options provided as the correct answer does not match the calculated result.
- The length of the filament of a heater is reduced by 10%.
**To Find:**
- The percentage change in the power of the heater.
**Solution:**
Let's assume the initial length of the filament is L and the initial power of the heater is P.
**Step 1: Calculate the new length of the filament after reducing it by 10%:**
The length of the filament after reducing it by 10% can be calculated as:
New Length = L - (10/100)L = L - 0.1L = 0.9L
**Step 2: Calculate the new power of the heater:**
We know that the power of a heater is directly proportional to the square of its length.
Therefore, the new power can be calculated as:
New Power = (New Length)^2 = (0.9L)^2 = 0.81L^2
**Step 3: Calculate the percentage change in power:**
The percentage change in power can be calculated using the formula:
Percentage Change = (New Power - Initial Power) / Initial Power * 100
Substituting the values, we get:
Percentage Change = (0.81L^2 - P) / P * 100
**Step 4: Simplify the expression:**
To compare the percentage change with the given options, we need to simplify the expression.
Let's assume the initial length L = 1 for simplicity.
Initial Power = P = L^2 = 1^2 = 1
Substituting the values, we get:
Percentage Change = (0.81 - 1) / 1 * 100 = -19%
Since the percentage change is negative (-19%), this means that the power of the heater has decreased by 19% when the length of the filament is reduced by 10%.
Therefore, none of the given options (a), (b), (c), or (d) are correct.
Please recheck the question and options provided as the correct answer does not match the calculated result.
|
Explore Courses for Class 12 exam
|
|
Similar Class 12 Doubts
If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer?
Question Description
If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer? for Class 12 2024 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer? covers all topics & solutions for Class 12 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer?.
If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer? for Class 12 2024 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer? covers all topics & solutions for Class 12 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer?.
Solutions for If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 12.
Download more important topics, notes, lectures and mock test series for Class 12 Exam by signing up for free.
Here you can find the meaning of If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer?, a detailed solution for If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer? has been provided alongside types of If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice If the length of the filament of a heater is reduced by10%the power of the heater willa)increase by about 11%b)increase by about 19%c)decrease by about 29%d)Increase by about 9%Correct answer is option 'A'. Can you explain this answer? tests, examples and also practice Class 12 tests.
|
|
Explore Courses for Class 12 exam
|
|
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
|
© EduRev
|
Education Revolution
|
Follow Us
|
Signup to see your scores
go up within 7 days!
Access 1000+ FREE Docs, Videos and Tests
Takes less than 10 seconds to signup