The harmonic frequency of a musical instrument is the minimum frequency at which a string that is fixed at both ends in the instrument may vibrate. The harmonic frequency is known as the first harmonic. Each subsequent harmonic has a frequency equal to:
n*f, where n is the number of the harmonic and f is the harmonic frequency. Therefore, the harmonic frequency may be calculated using:
f = 100 / 2
f = 50 Hz
Answer:

Explanation:
Velocity of the ship is given as

the direction of the velocity of the ship is making an angle of 11 degree with the current
so we will have two components of the velocity
1) along the direction of the current
2) perpendicular to the direction of the current
so here we know that the component of the ship velocity along the direction of the current is given as



Work done is the distance a force acts over.
So, the work done here is 9.0N * 3.0m = 27 J
Answer:
20 V
Explanation:
Power is 100 J/s or 100 W.
We know that P = IV =
.
Isolate the potential difference. V =
=
= 20 V
Answer:
c) Very dangerous and users must not override devices designed to protect from exposures.
Explanation:
X-ray is a form of high energy electromagnetic radiation and are part of the electromagnetic spectrum.
X-ray radiation from diffraction and fluorescence instruments is very dangerous because of their high energy and wavelength.
Hence, users must not override devices designed to protect from exposures. The best shielding device to protect one from exposure is Lead.