Using the principle of floatation.
u = w............(a)
Upthrust of fluid is equal to the weight of the object.
Let the volume of the wood be V.
The upthrust u, is related to the volume submerged in water, and that is 1/5 of it volume, that is (1/5)V = 0.2V
Formula for upthrust, u = vdg
where v = volume of fluid displaced
d = density of fluid
g = acceleration due to gravity
weight, w = mg
where m = mass
g = acceleration due to gravity
From (a)
u = w
vdg = mg Cancel out g
vd = m
The v is equal to 0.2V, which is the submerged volume. Notice that the small letter v is volume of fluid displaced, and capital V is the volume of the solid.
d is density of fluid which is water in this case, 1000 kg/m³
0.2V * 1000 = m
200V = m
Hence the mass of the object is 200V kg.
But Density of solid = Mass of solid / Volume of solid
= 200V / V
= 200 kg/m³
Density of solid = 200 kg/m³
Answer:The change in entropy of the total amount of water is negative as a result of the mixing.
Explanation:If you increase temperature, you increase entropy
Also More energy gives you greater entropy and randomness of the atoms.
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Formula which describes v in terms of t is 
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Explanation:
A train travels the distance between the points A and B, which is 600 km
Distance between A and B = 600 km
Speed of train = v
Time taken by train = t
We know that
Distance traveled = Speed of travel x Time taken
600 = v x t

Formula which describes v in terms of t is 
The induced emf in the loop is -1500 μ V or - 0.0015 V .
According to the question
A conducting loop in the form of a circle is placed perpendicular to a magnetic field of 0. 50 t.
i.e
Magnetic field (B) = 0. 50 T
Area of circle or loop =
Now,
The area of the loop decreases at a rate of 3. 0 × 10⁻³ m/s
i.e
dA = 3. 0 × 10⁻³ meter²
dt = 1 sec
As per the formula of Induced e.m.f in the loop
emf is dependent on number of turns of coil, shape of the coil, strength of magnet and speed with which magnet is moved. Emf is independent of resistivity of wire of the coil.

where A is the area of the loop.
Now ,
Substituting the values in the formula
e = - 0.0015 V
OR
e = -1500 * 10⁻⁶ V
e = -1500 μ V
Negative just signifies emf will such be induced that current induced will oppose change in magnetic field though it
To know more about induced emf here:
brainly.com/question/16764848
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