Answer:
The book sitting on the desk
Explanation:
The gravitational potential energy of an object is the energy possessed by the object due to its position relative to the ground.
It is calculated as:
where
m is the mass of the object
g is the acceleration due to gravity
h is the height of the object with respect to the ground
From the formula, we see that the GPE of an object is directly proportional to the heigth h: so, the higher the location of the object, the larger the GPE.
In this problem, we are comparing a book sitting on a desk and the same book sitting on the floor. In the two situations, the mass of the book is the same; however, in the first case, the value of the height is h, while in the second case, the value of h is lower (because the book is located at a lower height, being on the floor).
Therefore, we can conclude that the first book must have a larger GPE, since it has a larger value of h.
Answer:
0.550
Explanation:
The absorbance (A) of a substance depends on its concentration (c) according to Beer-Lambert law.
A = ε . <em>l</em> . c
where,
ε: absorptivity of the species
<em>l</em>: optical path length
A 45 mM phosphate solution (solution A) had an absorbance of 1.012.
A = ε . <em>l</em> . c
1.012 = ε . <em>l</em> . 45 mM
ε . <em>l</em> = 0.022 mM⁻¹
We can find the concentration of the second solution using the dilution rule.
C₁ . V₁ = C₂ . V₂
45mM . 11mL = C₂ . 20.0 mL
C₂ = 25 mM
The absorbance of the second solution is:
A = (ε . <em>l</em> ). c
A = (0.022 mM⁻¹) . 25 mM = 0.55 (rounding off to 3 significant figures = 0.550)
Answer:
d.-379 cal/mol
Explanation:
ΔG = ΔG⁰ + RT ln K
for equilibrium ΔG = 0
ΔG⁰ + RT ln K =0
ΔG⁰ = - RT ln K
PG ⇒ PEP
K = [ PEP ] / [ PG ]
= .68 / .32
= 2.125
ΔG⁰ = - 1.987 x 273 x ln 2.125
= - 409 Cal / mole
Option d is the nearest answer .
Answer:
1.61%.
Explanation:
The following data were obtained from the question:
Measured mass = 3.15 g.
Actual mass = 3.10 g
Percentage error =.?
The percentage error of the group can be obtained by using the following equation below:
Percentage error = |Actual mass – Measured mass| / Actual mass × 100
Percentage error = |3.10 – 3.15| /3.10 × 100
Percentage error = 0.05/3.1 × 100
Percentage error = 5/3.1
Percentage error = 1.61%
Therefore, the percentage error of the group is 1.61%.
