a substance dissolves.
like adding a soluble salt to water, it just dissolves, i.e dissociates homogeneously as water is able to dissociate salts (ionic compounds) into its ions. (it can also dissociate other non-ionic compounds like HCL)
the salt still remains chemically as a salt and is unchanged chemically thus it is not an indication of a chemical reaction as no chemical reaction has taken place.
the formation of a precipitate is a chemical reaction because a new substance (i.e new chemical) is formed. For example adding aqueous sodium hydroxide into an aqueous solution with CU2+ cations will form a blue precipitate (that is copper (II) hydroxide which is insoluble, hence it precipitates). Since a new chemical is formed, a chemical reaction has taken place and thus indicates a chemical reaction.
color change... im not sure but usually a color change will only occur when a new substance is formed. Like iron corrodes (i.e rust) slowly in moist air to form hydrated iron (III) oxide that is rust. (brown color).
usually adding a mixture to a mixture has little energy change, i.e little heat taken in by the reaction mixture or little heat given out by the reaction mixture. Whereas when a new substance is formed, there is usually noticeable energy change like the container gets colder or hotter (without heat being supplied of course). For example dissolving basic oxides into water releases energy ( more energy released than gained = exothermic reaction).
i think that should be the answer... hope it helped :D
Static equilibrium means that all forces are equal, so make this easiest you want to break F1 into it's horizontal and vertical components. As there are no other forces acting in the horizontal, we know the horizontal component of F1 is 40N. This allows the vertical component to be found using pythagorus theorem. After finding the vertical and horizontal components, you just have to add the vertical components to find the difference between the up and down.
They create energy ……………….
The loudness of the sound at the rock concert, where the intensity of the sound is1 x 10⁻¹ Wm⁻² is 110 dB.
Here we are dealing with loudness which is the perception of the Intensity of the sound.
The formula to refer to in order to find the value of the loudness of a sound is ,
db= 10log(I/I₀)
As we are provided with the current intensity which is 1 x 10⁻¹ Wm⁻². and the initial intensity which is 1 x 10⁻¹² Wm⁻².
So, by substituting the required values in the formula we get
db= 10 * log( 1 x 10⁻¹ /1 x 10⁻¹²)
= 10 * 11 log(10)
= 110
So, the result is 110 dB.
To know more about the intensity of sound refer to the link brainly.com/question/9323731?referrer=searchResults.
To know more about questions related to loudness refer to the link brainly.com/question/21094511?referrer=searchResults.
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Answer:
a) -2.038 m/s²
b) 40.33 mph
c) 312.5 m
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration

Acceleration of the boat is -2.083 m/s² if the boat will stop at 150 m.

Speed of the boat by when it will hit the dock is 18.03 m/s
Converting to mph



Speed of the boat by when it will hit the dock is 40.33 mph

The distance at which the boat will have to start decelerating is 312.5 m