Answer:
Option (B) is correct.
Explanation:
Given that the molecules of hydrogen gas (
) react with molecules of oxygen gas (
) in a sealed reaction chamber to produce water (
).
The governing equation for the reaction is
From the given, the only fact that can be observed that 2 moles of and 1 mole of reacts to produce 2 moles of .
As the mass of 1 mole of 
grams ... (i)
The mass of 1 mole of 
grams ...(ii)
The mass of 1 mole of 
grams (iii)
Now, the mass of the reactant = Mass of 2 moles of + mass 1 mole of
[ using equations (i) and (ii)]
grams.
Mass of the product = Mass of 2 moles of
[ using equations (iii)]
=36 grams
As the mass of reactants = mass of the product.
So, mass is conserved.
Hence, option (B) is correct.
Answer:
20 meters.
Explanation:
In the graph, the x-axis (the horizontal axis) represents the time, while the y-axis (the vertical axis) represents the distance.
If we want to find the distance covered in the first T seconds, you need to find the value T in the horizontal axis.
Once you find it, we draw a vertical line, in the point where this vertical line touches the graph, we now draw a horizontal line. This horizontal line will intersect the y-axis in a given value. That value is the total distance travelled by the time T.
In this case, we want to find the total distance that David ran in the first 4 seconds.
Then we need to find the value 4 seconds in the horizontal axis. Now we perform the above steps, and we will find that the correspondent y-value is 20.
This means that in the first 4 seconds, David ran a distance of 20 meters.
You get a lot of detailed information. hope this helped :)
Answer:
W = 0.135 N
Explanation:
Given:
- y (x, t) = 8.50*cos(172*x -2730*t)
- Weight of string m*g = 0.0126 N
- Attached weight = W
Find:
The attached weight W given that Tension and W are equal.
Solution:
The general form of standing mechanical waves is given by:
y (x, t) = A*cos(k*x -w*t)
Where k = stiffness and w = angular frequency
Hence,
k = 172 and w = 2730
- Calculate wave speed V:
V = w / k = 2730 / 172 = 13.78 m/s
- Tension in the string T:
T = Y*V^2
where Y: is the mass per unit length of the string.
- The tension T and weight attached W are equal:
T = W = Y*V^2 = (w/L*g)*V^2
W = (0.0126 / 1.8*9.81)*(13.78)^2
W = 0.135 N
the International System of Units, the fundamental units are: The meter (symbol: m), used to measure length. The kilogram (symbol: kg), used to measure mass. The second (symbol: s), used to measure time. The ampere (symbol: A), used to measure electric current.
