Answer:
Explanation:
Given that,
Initial angular velocity is 0
ωo=0rad/s
It has angular velocity of 11rev/sec
ωi=11rev/sec
1rev=2πrad
Then, wi=11rev/sec ×2πrad
wi=22πrad/sec
And after 30 revolution
θ=30revolution
θ=30×2πrad
θ=60πrad
Final angular velocity is
ωf=18rev/sec
ωf=18×2πrad/sec
ωf=36πrad/sec
a. Angular acceleration(α)
Then, angular acceleration is given as
wf²=wi²+2αθ
(36π)²=(22π)²+2α×60π
(36π)²-(22π)²=120πα
Then, 120πα = 8014.119
α=8014.119/120π
α=21.26 rad/s²
Let. convert to revolution /sec²
α=21.26/2π
α=3.38rev/sec
b. Time Taken to complete 30revolution
θ=60πrad
∆θ= ½(wf+wi)•t
60π=½(36π+22π)t
60π×2=58πt
Then, t=120π/58π
t=2.07seconds
c. Time to reach 11rev/sec
wf=wo+αt
22π=0+21.26t
22π=21.26t
Then, t=22π/21.26
t=3.251seconds
d. Number of revolution to get to 11rev/s
∆θ= ½(wf+wo)•t
∆θ= ½(0+11)•3.251
∆θ= ½(11)•3.251
∆θ= 17.88rev.
Answer:
a
Generally from third equation of motion we have that
![v^2 = u^2 + 2a[s_i - s_f]](https://tex.z-dn.net/?f=v%5E2%20%3D%20%20u%5E2%20%2B%202a%5Bs_i%20-%20s_f%5D%20)
Here v is the final speed of the car
u is the initial speed of the car which is zero
is the initial position of the car which is certain height H
is the final position of the car which is zero meters (i.e the ground)
a is the acceleration due to gravity which is g
So
=> 
b
Explanation:
Generally from third equation of motion we have that
![v^2 = u^2 + 2a[s_i - s_f]](https://tex.z-dn.net/?f=v%5E2%20%3D%20%20u%5E2%20%2B%202a%5Bs_i%20-%20s_f%5D%20)
Here v is the final speed of the car
u is the initial speed of the car which is zero
is the initial position of the car which is certain height H
is the final position of the car which is zero meters (i.e the ground)
a is the acceleration due to gravity which is g
So
=> 
When
we have that

=> 
=>
Answer : The wavelength of photon is, 
Explanation : Given,
Energy of photon = 
Formula used :

As, 
So, 
where,
= frequency of photon
h = Planck's constant = 
= wavelength of photon = ?
c = speed of light = 
Now put all the given values in the above formula, we get:


Conversion used : 
Therefore, the wavelength of photon is, 
Efficiency = useful energy out / total energy in x 100
= 100/400 x 100
=0.25 x 100
= 25%
25%
Newtons law of gravitation is called the universal law of gravitation because it is applicable for all masses at all distances, independent of the medium.