You need 5 blocks of the smaller object to contain the same amount of volume of the bigger object
In order to answer this question, I realized that I needed to know the index
of refraction for ruby, so I went and looked it up. It's 1.762 to 1.770 .
I started trying to remember how to use this number and the critical angle
to find the index of refraction of the other medium. That's when I saw the
absurd unit "degrees celsius" for the critical angle, and I got discouraged.
But I perked up very quickly, when I realized that I'm still on the "index of
refraction" list, and while I'm there, I might as well just go ahead and
look up ethyl alcohol too.
It's 1.36 .
Answer:
a) 5.22 m/s
b) 31.4 %
Explanation:
f = rotating speed = 15 rpm = 15/60 =0.25 rps
m = Mass flow rate of air = 42000 kg/s
v = Tip velocity = 250 km/h = 250/3.6 = 69.44 m/s
W = Work output = 180 kW
A = Swept area of wind turbine
r = Radius of wind turbine
η = Efficiency



∴ The average velocity of the air is 5.22 m/s


∴ Conversion efficiency of the turbine is 0.314 or 31.4 %
Answer:
The tension in string will be "3.62 N".
Explanation:
The given values are:
Length of string:
l = 3 ft
or,
= 0.9144 m
frequency,
f = 60 Hz
Weight,
= 0.096 lb
or,
= 0.0435 kgm/s²
Now,
The mass will be:
= 
= 
As we know,
⇒ 
On substituting the values, we get
⇒ 
⇒ 
or,
⇒ 
⇒ 
⇒ 
Now,
⇒ 
or,
⇒ 
On putting the above given values, we get
⇒ 
⇒ 
⇒ 
Answer:
Explanation:
Area of crossection, A = 7.80 cm²
Initial magnetic field, B = 0.5 T
Final magnetic field, B' = 3.3 T
Time, t = 1 s
resistance of the coil, R = 1.2 ohm
The induced emf is given by

where, Ф is the rate of change of magnetic flux.
e = 7.80 x 10^-4 x (3.3 - 0.5) / 1
e = 2.184 mV
i = e/R
i = 2.184/1.2
i = 1.82 mA