Q80.Twenty meters of wire is available for fencing off a flower-bed in the form of a circular sector. Then the maximum area (in sq. m) of the flower-bed, is: (1) 12 . 5 (2) 10 (3) 25 (4) 30
What This Question Tests
This question tests the ability to set up an optimization problem for the area of a circular sector given a fixed perimeter, and then use differentiation to find the maximum area.
Concepts Tested
Formulas Used
Area of sector A = (1/2)r^2ฮธ
Perimeter P = 2r + rฮธ
dA/dr = 0 for extremum
๐ NCERT Sections This Tests
4.8 โ A Closely Wound Solenoid 80 Cm Long Has 5 Layers Of Windings Of 400
Physics Class 11 ยท Chapter 4
4.8 A closely wound solenoid 80 cm long has 5 layers of windings of 400 turns each. The diameter of the solenoid is 1.8 cm. If the current carried is 8.0 A, estimate the magnitude of B inside the solenoid near its centre.
9.5 โ A Small Bulb Is Placed At The Bottom Of A Tank Containing Water To A
Physics Class 12 ยท Chapter 9
9.5 A small bulb is placed at the bottom of a tank containing water to a depth of 80cm. What is the area of the surface of water through which light from the bulb can emerge out? Refractive index of water is 1.33. (Consider the bulb to be a point source.)
9.18 โ For Fixed Distance S Between Object And Screen, The Lens Equation
Physics Class 12 ยท Chapter 9
9.18 For fixed distance s between object and screen, the lens equation does not give a real solution for u or v if f is greater than s/4. Therefore, fmax = 0.75 m.
๐ Question Details
- Chapter
- Applications of Derivatives
- Topic
- Maxima and Minima
- Year
- 2017
- Shift
- 02 Apr
- Q Number
- Q80
- Type
- MCQ
- NCERT Ref
- Class 12 Mathematics Ch 6: Applications of Derivatives
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