Answer:
The angular velocity of the propeller is 2.22 rad/s.
Explanation:
The angular velocity (ω) of the propeller is:
Where:
θ: is the angular displacement = 10.6 revolutions
t: is the time = 30 s

Therefore, the angular velocity of the propeller is 2.22 rad/s.
I hope it helps you!
Answer: 7.07 m/s
Explanation:
Mass of runner = 60 kg runner
Kinetic energy = 1500J
Speed of runner = ?
Recall that kinetic energy is the energy possessed by a moving object, and it depends on its mass and speed by which it moves.
Hence, K.E = 1/2 x mass x (speed)^2
1500J = 1/2 x 60kg x (speed)^2
1500J = 30kg x (speed)^2
(speed)^2 = 1500J/30kg
(speed)^2 = 50
To get the value of speed, find the square root of 50
speed = √50
speed = 7.07 m/s
Thus, the runner moves as fast as 7.07 m/s
Wavelength = 20 m = 0.20 m
frequency = 3*10^8 / 0.20 = 1.5 * 10^9 Hertz