Answer:
Option B
Explanation:
I did a question like this a long time ago so i'm not sure if its right so sorry if its wrong
Answer:
66.02m/s
Explanation:
the equation describing the distance covered in the horizontal direction is
but the acceleration in the horizontal path is zero, hence we have
Since the horizontal distance covered is 155m at 7.6secs, we have 
Also from the vertical path, the distance covered is expressed as
since the horizontal distance covered in 7.6secs is 195m, then we have
Hence if we divide both equation 1 and 2 we arrive at
Hence if we substitute the angle into the equation 1 we have
Hence the initial velocity is 66.02m/s
Actually Welcome to the concept of Efficiency.
Here we can see that, the Input work is given as 2.2 x 10^7 J and the efficiency is given as 22%
The efficiency is => 22% => 22/100.
so we get as,
E = W(output) /W(input)
hence, W(output) = E x W(input)
so we get as,
W(output) = (22/100) x 2.2 x 10^7
=> W(output) = 0.22 x 2.2 x 10^7 => 0.484 x 10^7
hence, W(output) = 4.84 x 10^6 J
The useful work done on the mass is 4.84 x 10^6 J
Answer:
- <u><em>Option A) A gas was produced.</em></u>
Explanation:
Indeed, the production of a gas is an indication that a new substance was produced as result of the reaction of the matter that constitutes the antiacid tablet and the distilled water.
A chemical reaction is a change that yields the formation of new substances (products), due to the rearrangements of the atoms of the reactants.
In a very simple form, you can represent a chemical reaction by the general equation:
Which means that some elements or compounds, those in the reactant side of the equation, undergo a change in which some chemical bonds are broken, the atoms separate from the original substances and combine into a new arrangement in which they form one or more different substances (products).
The option B), that the table dissapeared is not a clear evidence of a chemical change because it could have been dissolved, which is a physical change.
Also, the option C), that there was a color change, cannot be cited as an evidence of a chemical reaction, since the color is a physical property.
As for the option D, that there was a change in mass, is not a viable option, since mass cannot change either with a chemical or physical change.
