Answer:
O B. when the angle between the force and displacement is 90°
Explanation:
<h3>work defined as

. </h3><h3>work can only be done if object moves(displacement) in the direction of force. now a quick one. if you since the varrious angles into the cosine, you would see that Cos 90 will give zero which implies that no work is done. Again, angle means it is perpendicular and so it is not in the direction of force.</h3>
Out of the choices given, the tool that would be best for Diana to use is the light microscope. The correct answer is B.
Complete question:
A taut rope has a mass of 0.123 kg and a length of 3.54 m. What average power must be supplied to the rope to generate sinusoidal waves that have amplitude 0.200 m and wavelength 0.600 m if the waves are to travel at 28.0 m/s ?
Answer:
The average power supplied to the rope to generate sinusoidal waves is 1676.159 watts.
Explanation:
Velocity = Frequency X wavelength
V = Fλ ⇒ F = V/λ
F = 28/0.6 = 46.67 Hz
Angular frequency (ω) = 2πF = 2π (46.67) = 93.34π rad/s
Average power supplied to the rope will be calculated as follows

where;
ω is the angular frequency
A is the amplitude
V is the velocity
μ is mass per unit length = 0.123/3.54 = 0.0348 kg/m
= 1676.159 watts
The average power supplied to the rope to generate sinusoidal waves is 1676.159 watts.
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