Answer:
Let the volume of the block of wood be
V
c
m
3
and its density be
d
w
g
c
m
−
3
So the weight of the block
=
V
d
w
g
dyne, where g is the acceleration due to gravity
=
980
c
m
s
−
2
The block floats in liquid of density
0.8
g
c
m
−
3
with
1
4
t
h
of its volume submerged.So the upward buoyant force acting on the block is the weight of displaced liquid
=
1
4
V
×
0.8
×
g
dyne.
Hence by cindition of floatation
V
×
d
w
×
g
=
1
4
×
V
×
0.8
×
g
⇒
d
w
=
0.2
g
c
m
-3
,
Now let the density of oil be
d
o
g
c
m
-3
The block floats in oil with 60% of its volume submerged.So the buoyant force balancing the weight of the block is the weight of displaced oil =
60
%
×
V
×
d
o
×
g
dyne
Now applying the condition of floatation we get
60
%
×
V
×
d
o
×
g
=
V
×
d
w
×
g
⇒
60
100
×
V
×
d
o
×
g
=
V
×
0.2
×
g
⇒
d
o
=
0.2
×
10
6
=
1
3
=
0.33
g
c
m
−
3
Explanation:
From the equation of the graph, the activation energy of the reaction is -2.2 * 10⁴ J/mol.
<h3>What is activation energy?</h3>
Activation energy is the minimum required energy that reactant molecules must possess for a reaction to proceed towards formation of products.
The activation energy is determined from the slope of ln k against 1/T(K).
Given the equation, y = -2.2 * 10⁴ x + 45.0.
Comparing with the equation of a straight line, y = mx + c
The gradient, m = -2.2 * 10⁴
Therefore, the activation energy of the reaction is -2.2 * 10⁴ J/mol.
In conclusion, reactant molecules must break the activation energy barrier in order to form products.
Learn more about activation energy at: brainly.com/question/26724488
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Dissolved organic substance present in natural water is a complex mixture compounds and contains most of the reduced carbon present in aquatic ecosytem . this can not be easily treated or disinfected by the conventional treatment . the experiments show that water sample with higher dissolved substance need higher cholrine demand . this is the reason that before disinfecting with chlorine ..... need to remove organic substance {{{ because it increase chlorine demand }}}
Answer:
Ethos, because she is using her own knowledge as a tool.
Explanation:
Harriet Tubman was an activist and served as a spy for Union Army. <u>'Harriet Tubman: Conductor on the Underground Railroad'</u> is a book written by Ann Petry narrating the accounts of life of Harriet Tubman who helped free 300 slaves using the paths of Underground Railroad.
In the given excerpt, Tubman has used the rhetorical appeal of 'ethos' as she is using her own knowledge as a tool. While rescuing slaves using Underground Railroad, Tubman made up several stories to keep the slaves moving and encourage them in their paths of freedom. The path for freedom was dangerous, and Tubman knew that some may back up from this, so she kept telling them about people who chose to struggle for freedom, made up stories about them and used this knowledge as a tool to keep the slaves encouraged and motivated. And no one asked her even one question as they trusted her (credibility-- element of ethos).
Thus, the tool Tubman has used in the given excerpt is ethos.
There would be 7- this would be the process of meiosis, which would result in 4 haploid cells (each would have half the number of chromosomes as the parent (or 7), as meiosis is sex cell division) the other type of cell division is called mitosis and results in two daughter cells identical to the parent cell (2 cells, each with 14 chromosomes)