Answer:

Explanation:
As we know that the angle of incidence is given as

also we have angle of refraction as

now by Snell's law we know that


now we have


Answer:
Diffraction of sound wavelengths.
Explanation:
-A wave is able to bend around a corner due to the effects of diffraction. sound aves are capable of bending around corners in the same magnitude as it's wavelength making it possible to hear sounds around corners.
Answer:
Explanation:
a )
hear energy required to melt 1 g of ice = 340 J ,
hear energy required to melt 80 g of ice = 340 x 80 J = 27220 J .
b ) energy gained by the melted ice ( water at O°C ) = m ct
where m is mass of water , s is specific heat and t is rise in temperature
= 80 x 4.2 x ( 8°C - 0°C)
= 2688 J .
c )
energy lost by lime juice = energy gained by ice and water
= 27220 J + 2688 J .
= 29908 J .
d )
Let specific heat required be S
Heat lost by lime juice = M S T
M is mass of lime juice , S is specific heat , T is decrease in temperature
= 320 g x S x ( 29 - 8 )°C
= 6720 S
For equilibrium
Heat lost = heat gained
6720 S = 29908 J
S = 4.45 J /g °C .
Answer:
a soft foam material because soft materials absorb sound better