<span>The multiple reflection of a single sound wave is echo</span>
Answer:
Explanation:
As the source is situated on x - axis , it must be situated in between the two listeners .
So the x coordinate of source is
(-7 + 3 )/2
= - 2 m
The equation of the wave- front will be that o a circle having centre at (-2,0)
and radius = distance between -2 and 3 , that is 5 m
equation of circle
=( x+2 )² + y² = 25
It cuts y axis when x = 0
Putting x = 0
4 + y² = 25
y² = 21
y = + √21 , or - √21
I dont know but i know i dont lnow if this is true but the gravity is slowly going away every 4 year i dont know i think.
Answer:
33 g.
Explanation:
Assuming no heat transfer can be possible except for heat exchange between water and steel, we can say that the heat lost by the knife, must be equal to the heat gained by the water.
As we have a limit for the maximum temperature of both elements (once reached a final thermal equilibrium), of 100ºC, which means that the maximum allowable change in temperature will be of 300º C for the knife, and of 80º C for the water.
Empirically , it has been showed that for a heat exchange process using only conduction, the heat needed to raise the temperature of a body, is proportional to the mass, being the proportionality constant a factor that depends on the material, called specific heat.
So, we can write the following equation:
cs*mk*Δtk = cw*mw*Δtw
Replacing by the givens of the question, we have:
0.11 cal/gºC * 80 g * 300ºC = 1 cal/gºC*mw*80ºC
Solving for mw = 2,640 cal / 80 cal/g =33 g.
The possible resulting chemical formulas for an ionic compound with calcium given the respective charges of the ions are: CaO, CaMg, or CaF₂ and CaO, CaF₂, or CaCl₂. This is because when dealing with these compounds, you simply need to interchange the oxidation state of the two elements and place as the subscript of the element. For instance, when we have Ca²⁺ and F⁻, the result is CaF₂. However, when the oxidation states of the two compounds are equal, the subscript is 1. That is, for Ca²⁺ and Mg²⁻, the result is CaMg. And for Ca²⁺ and Cl⁻, the result is CaCl₂.
