I'll be happy to solve the problem using the information that
you gave in the question, but I have to tell you that this wave
is not infrared light.
If it was a wave of infrared, then its speed would be close
to 300,000,000 m/s, not 6 m/s, and its wavelength would be
less than 0.001 meter, not 12 meters.
For the wave you described . . .
Frequency = (speed) / (wavelength)
= (6 m/s) / (12 m)
= 0.5 / sec
= 0.5 Hz .
(If it were an infrared wave, then its frequency would be
greater than 300,000,000,000 Hz.)
You use acceleration due to gravity
and 1/2 atsqr=d
therefore 1/2 * 9.8 * tsqr= d
Answer:
70 cm
Explanation:
0.5 kg at 20 cm
0.3 kg at 60 cm
x = Distance of the third 0.6 kg mass
Meter stick hanging at 50 cm
Torque about the support point is given by (torque is conserved)

The position of the third mass of 0.6 kg is at 20+50 = 70 cm
Vertical force on the box=mg
<span>the component of gravity parallel=mg*SinTheta </span>
<span>the component of gravity normal=mg*CosTheta </span>
<span>frictional force up the plane: mg*cosTheta*mu max, but if it is sitting still, it is equal and opposite to mg*cosTheta (it cannot be greater than this or it would go up the plane).</span>