Q27.A copper ball of radius 1 cm and work function 4.47 eV is irradiated with ultraviolet radiation of wavelength 2500 Å . The effect of irradiation results in the emission of electrons from the ball. Further the ball will acquire charge and due to this there will be a finite value of the potential on the ball. The charge acquired by the ball is : (1) 5.5 × 10−13 C (2) 7.5 × 10−13 C (3) 4.5 × 10−12 C (4) 2.5 × 10−11 C
What This Question Tests
This multi-concept problem requires calculating the maximum kinetic energy of emitted photoelectrons, determining the stopping potential, and then using this potential to find the charge accumulated on a spherical conductor.
Concepts Tested
Formulas Used
E = hc/λ
K_max = E - Φ
K_max = eV_stop
Q = CV = (4πε₀R)V_stop
📚 NCERT Sections This Tests
11.7 — The Work Function For A Certain Metal Is 4.2 Ev. Will This Metal Give
Physics Class 12 · Chapter 11
11.7 The work function for a certain metal is 4.2 eV. Will this metal give hotoelectric emission for incident radiation of wavelength 330 nm?
11.9 — Light Of Wavelength 488 Nm Is Produced By An Argon Laser Which Is
Physics Class 12 · Chapter 11
11.9 Light of wavelength 488 nm is produced by an argon laser which is used in the photoelectric effect. When light from this spectral line is incident on the emitter, the stopping (cut-off) potential of photoelectrons is 0.38 V. Find the work function of the material from which the emitter is made.
11.3 — The Photoelectric Cut-Off Voltage In A Certain Experiment Is 1.5 V.
Physics Class 12 · Chapter 11
11.3 The photoelectric cut-off voltage in a certain experiment is 1.5 V. What is the maximum kinetic energy of photoelectrons emitted?
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- Photoelectric effect
- Year
- 2013
- Shift
- 25 Apr Online
- Q Number
- Q27
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Radiation and Matter
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