Answer:
Frequency of the light will be equal to 
Explanation:
We have given wavelength of the light 
Velocity of light is equal to 
We have to find the frequency of light
We know that velocity is equal to 
, here 
is wavelength and f is frequency of light
So frequency of light will be equal to 
So frequency of the light will be equal to
Answer: 71.7 KJ
Explanation:
The rotational kinetic energy of a rotating body can be written as follows:
Krot = ½ I ω2
Now, any point on the rim of the flywheel, is acted by a centripetal force, according to Newton’s 2nd Law, as follows:
Fc = m. ac
It can be showed that the centripetal acceleration, is related with the angular velocity and the radius, as follows:
ac = ω2 r
We know that this acceleration has a limit value, so , we can take this limit to obtain a maximum value for the angular velocity also.
As the flywheel is a solid disk, the rotational inertia I is just ½ m r2.
Replacing in the expression for the Krot, we have:
Krot= ½ (1/2 mr2.ac/r) = ¼ mr ac = ¼ 67.0 Kg. 1.22 m . 3,510 m/s2 = 71. 7 KJ
The sprinter’s average acceleration is 1.98 m/s²
The given parameters;
- initial velocity of the sprinter, u = 18 km/h
- final velocity of the sprinter, v = 27 km/h
- time of motion of the sprinter, t = 3.5 x 10⁻⁴ h
Convert the velocity of the sprinter to m/s;
The time of motion is seconds;
The sprinter’s average acceleration is calculated as follows;
Thus, the sprinter’s average acceleration is 1.98 m/s²
Learn more here:brainly.com/question/17280180
C: the mechanical energy isn't conserved. Some energy was lost to friction.
Explanation:
Given that,
Rate of cooling of air
Initial temperature= 80°C
Final temperature = 5°C
We need to calculate
Using newton's law of cooling
Where, 
Here, 
= 25°C (surrounding temperature)
dt = 1 minute
Put the value into the formula
Hence, This is the required answer.
