Answer:![u=4.51 m/s\ at\ angle\ of\ \theta =59.34^{\circ}](https://tex.z-dn.net/?f=u%3D4.51%20m%2Fs%5C%20at%5C%20angle%5C%20of%5C%20%5Ctheta%20%3D59.34%5E%7B%5Ccirc%7D)
Explanation:
Given
height of building h=3 m
Landing velocity of diver
at an angle of ![75^{\circ}](https://tex.z-dn.net/?f=75%5E%7B%5Ccirc%7D)
Let u be the initial velocity of diver at an angle of \theta with horizontal
Since there is no acceleration in horizontal direction therefore horizontal component of velocity will remain same
---- -----1
Considering Vertical motion
![v^2-u^2=2as](https://tex.z-dn.net/?f=v%5E2-u%5E2%3D2as)
here ![v=8.9\sin (75)](https://tex.z-dn.net/?f=v%3D8.9%5Csin%20%2875%29)
![s=3 m](https://tex.z-dn.net/?f=s%3D3%20m)
![a=9.8 m/s^2](https://tex.z-dn.net/?f=a%3D9.8%20m%2Fs%5E2)
![(8.9\sin (75))^2-(u\sin \theta )^2=2\times 9.8\times 3](https://tex.z-dn.net/?f=%288.9%5Csin%20%2875%29%29%5E2-%28u%5Csin%20%5Ctheta%20%29%5E2%3D2%5Ctimes%209.8%5Ctimes%203)
![u\sin \theta =\sqrt{(8.9\sin 75)^2-(2\cdot 9.8\cdot 3)}](https://tex.z-dn.net/?f=u%5Csin%20%5Ctheta%20%3D%5Csqrt%7B%288.9%5Csin%2075%29%5E2-%282%5Ccdot%209.8%5Ccdot%203%29%7D)
----------------2
Divide 2 and 1 we get
![\tan \theta =\frac{3.886}{8.9\cos (75)}](https://tex.z-dn.net/?f=%5Ctan%20%5Ctheta%20%3D%5Cfrac%7B3.886%7D%7B8.9%5Ccos%20%2875%29%7D)
![\tan \theta =1.687](https://tex.z-dn.net/?f=%5Ctan%20%5Ctheta%20%3D1.687)
![\theta =59.34^{\circ}](https://tex.z-dn.net/?f=%5Ctheta%20%3D59.34%5E%7B%5Ccirc%7D)
Thus ![u\cos (59.34)=8.9\cos (75)](https://tex.z-dn.net/?f=u%5Ccos%20%2859.34%29%3D8.9%5Ccos%20%2875%29)
![u=4.51 m/s](https://tex.z-dn.net/?f=u%3D4.51%20m%2Fs)
Answer:
(a) decrease
Explanation:
Viscosity is the resistance which occur to flow of the fluid.
More the inter molecular forces between particles of the liquid, more the viscosity of liquid.
<u>Effect of temperature on viscosity:-</u>
Viscosity decreases with the increase in the temperature as forces among the particles decrease on increasing temperature. The kinetic energy of the particles of the liquid increases causing to move in more random motions and thus weaker inter molecular forces and this offer less resistance to the flow.
<u>Hence, viscosity of the liquids decrease with the increasing temperature.</u>
![\huge\mathbb\colorbox{black}{\color{white}{⏫FORMULA⏫}}](https://tex.z-dn.net/?f=%5Chuge%5Cmathbb%5Ccolorbox%7Bblack%7D%7B%5Ccolor%7Bwhite%7D%7B%E2%8F%ABFORMULA%E2%8F%AB%7D%7D)
![\huge\red {\underline { \overline{ \bf \mid\: \: \: ↓ANSWER↓ \: \: \mid}}}](https://tex.z-dn.net/?f=%5Chuge%5Cred%20%7B%5Cunderline%20%7B%20%5Coverline%7B%20%5Cbf%20%5Cmid%5C%3A%20%5C%3A%20%20%5C%3A%20%E2%86%93ANSWER%E2%86%93%20%5C%3A%20%5C%3A%20%5Cmid%7D%7D%7D)
Explanation:
Snell's law (also known as Snell–Descartes law and the law of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, or air.
-- 'Ca' (Calcium) is an element.
-- The proton has a positive charge.
-- Nuclear fusion results in the synthesis of atoms of new elements.
-- H₂O (water) is a chemical compound.
-- Nuclear fission is a decay of the nucleus.
-- The atomic number of an element is the number of protons
in each atom of it.
-- I suppose you're using the Greek letter <span>η ('eta', not 'nu')
to represent the neutron.
-- I suppose you're using ' e ' to represent the electron.
</span>
Answer:
Laser
Explanation:
A laser is not a form of wave.