Answer:
W=0.94J
Explanation:
Electrostatic potential energy is the energy that results from the position of a charge in an electric field. Therefore, the work done to move a charge from point 1 to point 2 will be the change in electrostatic potential energy between point 1 and point 2.
This energy is given by:

So, the work done to move the chargue is:

The work is positive since the potential energy in 1 is greater than 2.
We know,
Speed = Frequency * Wavelength
Speed = 3 * 0.1 m/s [hertz = 1/sec.]
So, your final answer is 0.3 m/s
Hope this helps!!
Answer: The density of this piece of jewelry is 
Explanation:
To calculate the density, we use the equation:

Mass of piece of jewellery = 130.8 g
Density of piece of jewellery = ?
Volume of piece of jewellery =( 62.4-47.7 ) ml = 14.7 ml =

Putting values in above equation, we get:

Thus density of this piece of jewelry is 
Answer:When the length of a string is changed, it will vibrate with a different frequency.Shorter strings have higher frequency and therefore higher pitch.