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

What are three dimensional wave , Energy in transmitted in space in all dir...

Energy in transmitted in space in all direction. Example : Light and sound waves propagating in space.

Define the cylinders and heat bath, Define the Cylinders and Heat Bath? ...

Define the Cylinders and Heat Bath? Regard as a cylinder 1 m long with a thin, massless piston clamped in such a manner that it divides the cylinder into two equal parts. The

A see-saw lever, A see-saw lever Get a thick plank about 3 m long and b...

A see-saw lever Get a thick plank about 3 m long and bring it into the class room. Balance it over a box or some other suitable device and let the pupils experiment with the se

Longitudinal waves and guitar strings, Longitudinal Waves and Guitar String...

Longitudinal Waves and Guitar Strings According to the diagram this pressure wave consists of rarefactions and compressions. The compressions are regions of high pressure, wher

#title. entopy., what is entropy and how is it useful in our everyday life?...

what is entropy and how is it useful in our everyday life?

Experiments on inertia - a bottle and marble, A bottle and marble Pour ...

A bottle and marble Pour some sand into a wide mouthed bottle. Place a piece of cardboard about 5 cm square over the mouth of the bottle. Set the marble on the cardboard and th

What is the path of the beam in the magnetic field, Q. A beam of electrons ...

Q. A beam of electrons travelling with a speed of 4 X 10 7 ms -1 is projected normal to a magnetic field of B = 10 -3 Wb m -2 . What is the path of the beam in the magnetic fiel

Radioactive heat transfer, Consider a horizontal cylinder with L/D = large....

Consider a horizontal cylinder with L/D = large. Imagine this cylinder is filled with a liquid to different levels (consider cases where it is 10, 20, 50, 70, 90% full, note that l

Illustrate what does gravitational force depend on, Q. Illustrate what does...

Q. Illustrate what does gravitational force depend on? Answer:- The Gravitational force depends on distance as well as mass. Therefore the formula for calculating gravitat

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