Q16.The magnitude of the average electric field normally present in the atmosphere just above the surface of the Earth is about 150 N/C , directed inward towards the center of the Earth. This gives the total net surface charge carried by the Earth to be : [Given : ∈O= 8.85 × 10−12 C2/N-m2, RE = 6.37 × 106m] (1) −680 kC (2) + 670 kC (3) + 680 kC (4) − 670 kC
What This Question Tests
This question tests the ability to calculate the total charge on a spherical conductor (Earth) given the electric field just outside its surface, using Gauss's Law or the relation between electric field and surface charge density.
Concepts Tested
Formulas Used
E = |σ|/ε₀
Q = σ * 4πR²
Q = E * 4πε₀R²
📚 NCERT Sections This Tests
2.4 — A Spherical Conductor Of Radius 12 Cm Has A Charge Of 1.6 × 10–7C
Physics Class 11 · Chapter 2
2.4 A spherical conductor of radius 12 cm has a charge of 1.6 × 10–7C distributed uniformly on its surface. What is the electric field (a) inside the sphere (b) just outside the sphere (c) at a point 18 cm from the centre of the sphere?
1.16 — Careful Measurement Of The Electric Field At The Surface Of A Black
Physics Class 11 · Chapter 1
1.16 Careful measurement of the electric field at the surface of a black box indicates that the net outward flux through the surface of the box is 8.0 × 103 Nm2/C. (a) What is the net charge inside the box? (b) If the net outward flux through the surface of the box were zero, could you conclude that there were no charges inside the box? Why or Why not?
1.19 — A Point Charge Causes An Electric Flux Of –1.0 × 103 Nm2/C To Pass
Physics Class 11 · Chapter 1
1.19 A point charge causes an electric flux of –1.0 × 103 Nm2/C to pass through a spherical Gaussian surface of 10.0 cm radius centred on the charge. (a) If the radius of the Gaussian surface were doubled, how much flux would pass through the surface? (b) What is the value of the point charge?
📋 Question Details
- Chapter
- Electrostatics
- Topic
- Electric field and surface charge density
- Year
- 2014
- Shift
- 09 Apr Online
- Q Number
- Q16
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 1: Electric Charges and Fields
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