Answer:
<h3>The answer is option B</h3>
Explanation:
The frequency of a wave can be found by using the formula
where
c is the velocity
From the question
wavelength = 0.39 m
c = 86 m/s
We have
We have the final answer as
<h3>200 Hz</h3>
Hope this helps you
3x10^8 m/s, or the ‘speed of light’ - this applies to the entire spectrum
Answer:
T = 0.00889 N*m
Explanation:
Given the initial speed
Vo = 9.0rev/s.
V = 65 rev/10s
V = 6.5 rev/s.
V = Vo + a*t
Solve to acceleration knowing the initial velocity and the velocity at 10 s
6.5 rev/s - 9 rev/s = a*10s
a = -0.25 rev/s^2.
Now the solve the time at stop time so V=0
V = Vo + a*t
0 = 9.0 - 0.25 rev/s *t,
t = 36 s The Stopping time.
36s - 10s = 26s
The torque can be find using the acceleration using the equation
T = I*a
I = 1/2*m*r^2
I = 1/2*0.725kg*(0.315m)^2= 0.0359kg*m^2
T = 0.0359kg*m^2*-0.25rev/s^2
T = 0.00889 N*m
