# A 125 w b 160 w c 250 w d 500 w t e e t e t e t e t

• Homework Help
• 1364

Course Hero uses AI to attempt to automatically extract content from documents to surface to you and others so you can study better, e.g., in search results, to enrich docs, and more. This preview shows page 294 - 297 out of 1364 pages.

A125 WB160 WC250 WD500 WtEEtEtEtEt
1227A pendulum is driven by a periodic driving force of frequency f. The variation ofpendulum’s amplitude with driving frequency was determined for experiments done in acontainer of fixed volume of gas, and at two temperatures T1and T2.When T2> T1,determine which of the following graphs best illustrates how amplitude of the pendulumchanges with the driving frequency. (Viscosity of air increases with temperature).28A point source of sound emits energy equally in all directions at a constant rate and aperson 8 m from the source listens. After a while, the intensity of the source is doubled. Ifthe person wishes the sound to seem as loud as before, how far should he be standingnow?A2 mB22mC82mD28m29By blowing across the mouth of a glass bottle, the air column in the bottle can be made tovibrate and produce a tone. In order to tune the bottle and use it as a musical instrument, thefundamental frequency of the bottle must be 440 Hz. The bottle is 0.450 m tall and the speedof sound is 340 m s−1.How high should the bottle be filled with water?A0.064 mB0.193 mC0.257 mD0.386 m30When light of wavelength 570 nm is incident normally on a plane diffraction grating, thesecond-order diffraction images are formed at an angle of 34.8° to the normal of thegrating. What is the number of lines per millimetre of the grating?A500B1000C2000D50000031Transitions between three energy levels in a particular atom give rise to three spectrallines. The shortest and the longest wavelengths of these spectral lines are1and2respectively. The wavelength of the other spectral line isA2-1B212C 1212D 1221Driving frequencyT2T1Driving frequencyT1T2Driving frequencyT2T1Driving frequencyT1T2ABCD
1332The energy bands of three materials are shown below.Which of the following arranges correctly the materials in increasing order of resistance atroom temperature?APQRBRPQCQRPDQPR33Which of the following statements about laser production is correct?AStimulated emission is a key process because the photons produced have the samefrequency with a constant phase difference.BA metastable state is required so that there can be more stimulated emissions thanspontaneous emissions.CPopulation inversion is achieved when there are more atoms in the ground statethan in the excited state.DThe purpose of pumping is to trigger the occurrence of stimulated emissions.34Which of the following statements about a pn junction is correct?AAt the junction, the n-type semiconductor has a lattice of negative ions.BWhen the n-type semiconductor is connected to the positive terminal and the p-typesemiconductor is connected to the negative terminal of a battery, the depletionregion becomes narrower.

Course Hero member to access this document

Course Hero member to access this document

End of preview. Want to read all 1364 pages?

Course Hero member to access this document

Term
Winter
Professor
N/A