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

Force, a car has a mass of 34.01 kg. The race lasts 30 seconds. you think i...

a car has a mass of 34.01 kg. The race lasts 30 seconds. you think if the car attains an acceleration of .55 m/s^2 to attain a final velocity of 16.54m/s it will win the race. what

Action and reaction with a roller skate, Action and reaction with a roller ...

Action and reaction with a roller skate Place a roller skate on a smooth floor. Step on the roller skate with one foot and take a step forward with the other. Observe that the

Explain the meaning of lasers, Explain the meaning of Lasers? Lasers us...

Explain the meaning of Lasers? Lasers use these discrete energy levels in atoms or molecules to build a large population of atoms at an excited energy level that are ready and

Find larry''s gravitational potential energy, Larry's gravitational potenti...

Larry's gravitational potential energy is 1870Jas he sits 2.20 m above the ground in a sky diving airplane. What is Larry's gravitational potential energy when he begins to jump fr

No.of electrons in outermost orbt element of atomic number, Number of elect...

Number of electrons in the outermost orbit of the element of atomic number 15 is: (1) 1        (2) 3        (3) 5        (4) 7 Ans: 5

Light dependent resistor, These resistors change their resistance with vari...

These resistors change their resistance with variations of incident light energy. MANUFACTURING: Cadmium sulphide is obtained in a highly pure state. By adding special m

Explain applications of cement mortar, Applications of cement mortar 1....

Applications of cement mortar 1. It is used to carry out pointing and plaster works on exposed surface of masonry. 2. It is used to bind the building units like bricks, ston

Explain radio isotopes, What are radiation hazards? Mention four safety mea...

What are radiation hazards? Mention four safety measures which should be taken against radioactive radiation.  OR Explain radio isotopes? Write their any four uses. Descri

Ratio of masses of proton and electron is, Ratio of masses of proton and el...

Ratio of masses of proton and electron is: (1) Infinite (2) 1.8x10 3     (3) 1.8         (4) None of these Ans: (2) 1.8x10 3

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