the answer is B a freckle I just had this as a Study Island and got it right.
Answer:
Explanation:
a )
Each blade is in the form of rod with axis near one end of the rod
Moment of inertia of one blade
= 1/3 x m l²
where m is mass of the blade
l is length of each blade.
Total moment of moment of 3 blades
= 3 x x m l²
ml²
2 )
Given
m = 5500 kg
l = 45 m
Putting these values we get
moment of inertia of one blade
= 1/3 x 5500 x 45 x 45
= 37.125 x 10⁵ kg.m²
Moment of inertia of 3 blades
= 3 x 37.125 x 10⁵ kg.m²
= 111 .375 x 10⁵ kg.m²
c )
Angular momentum
= I x ω
I is moment of inertia of turbine
ω is angular velocity
ω = 2π f
f is frequency of rotation of blade
d )
I = 111 .375 x 10⁵ kg.m² ( Calculated )
f = 11 rpm ( revolution per minute )
= 11 / 60 revolution per second
ω = 2π f
= 2π x 11 / 60 rad / s
Angular momentum
= I x ω
111 .375 x 10⁵ kg.m² x 2π x 11 / 60 rad / s
= 128.23 x 10⁵ kgm² s⁻¹ .
Answer:
b. Both stars will have the same shift.
Explanation:
It's a very simple problem to solve. Star 1 is approaching toward Earth with a speed v, so let's assume that the change in Doppler Shift is +F and Star 2 is moving away so the change in Doppler shift is -F. But it's time to notice the speed of both stars and that is same but only directions are different. speed is the main factor here. The magnitude of both shifts is F as we can see and + and - are showing there direction of motion. So, because of same amount of speed, both stars will have same shift magnitude. (Just the directions are different)
A) 4.7 cm
The formula for the angular spread of the nth-maximum from the central bright fringe for a diffraction from two slits is
where
n is the order of the maximum
is the wavelength
is the distance between the slits
In this problem,
n = 5
So we find
And given the distance of the screen from the slits,
The distance of the 5th bright fringe from the central bright fringe will be given by
B) 8.1 cm
The formula to find the nth-minimum (dark fringe) in a diffraction pattern from double slit is a bit differente from the previous one:
To find the angle corresponding to the 8th dark fringe, we substitute n=8:
And the distance of the 8th dark fringe from the central bright fringe will be given by