Optics, Physics

Assignment Help:

A spider is hanging by means of its own silk thread directly above a transparent fixed sphere of r = 20cm .... the refractive index of material of sphere is root(2).... and height of the spider is 2r = 40cm .... an insect initially sitting at the bottom directly below the spider starts crawling along vertical circular path with constant speed pi/4 cm/s.. for how long will the insct be invisible to the spider. Assume that it crawls once around the circle .

Solution) Spider is able to see only half of the sphere which is topmost hemispherical surface. when insct enters in bottom hemispherical surface it becomes invisible for the spider. a/c question insct is travelling vertical circular path it travels pi/4cm in 1sec.then it will travel 2pi r dist i.e. 40picm in 160sec. hence it will travel pi r i.e20pi (half circle) in 80s.


Related Discussions:- Optics

Light absorbing materials in solar cells, All solar cells require a light a...

All solar cells require a light absorbing material contained within the cell structure to absorb photons and generate electrons via the photo voltaic effect. The materials used in

Determine the velocity of sound in sea water, An undersea explosion occurs...

An undersea explosion occurs. If the sea water has density 1.03 x 10 3 kg/m3 and Bulk Modulus of 2.41x10 9 Nm -2 ; a)  Determine the velocity of sound in sea water b)  If

Applications of superconductors, Applications of Superconductors - 1. El...

Applications of Superconductors - 1. Electrical Machines  2. Power Cables 3. Electro Magnets  4. Amplifiers 5. Cryotron 6. Magnetic Leviation 7. A 15 Phases

Relativity principle, Relativity principle: The principle, employed th...

Relativity principle: The principle, employed through Einstein's relativity theories, that the laws of physics are the similar, at least qualitatively, in all of frames. That

How much should be the voltage of an x-ray tube, Q. How much should be the ...

Q. How much should be the voltage of an X-ray tube so that the electrons emitted from the cathode may give an X-ray of wavelength 1 A o after striking the target?  λmin = 124

What is the ohm law, What is the Ohm Law? Ohm discovered that the amoun...

What is the Ohm Law? Ohm discovered that the amount of current was directly proportional to the voltage (more voltage gives more current) and inversely proportional to the resi

Spectrum and electromagnetic radiations, Spectrum and electromagnetic radia...

Spectrum and electromagnetic radiations: What is a spectrum? Ans: A spectrum is a group of wave lengths or frequencies. What  are the electromagnetic radiations? Ans:

Speed-time graph, A girl starts and finishes the ride at rest. Her horizont...

A girl starts and finishes the ride at rest. Her horizontal motion can be take as. •an initial uniform acceleration for 3.0s, followed by •a constant speed of 2.4m/s for a further

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd