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3 years ago

6

A block floats partially submerged in a container of liquid. When the entire container is accelerated upward, which of the follo

wing happens? Assume that both the liquid and the block areincompressible.
(A) The block descends down lower into the liquid.(B) The block ascends up higher in the liquid.(C) The block does not ascend nor descend in the liquid.
(D) The answer depends on the direction of motion of the container.(E) The answer depends on the rate of change of the acceleration

1 answer:

Nookie1986 [14]3 years ago

7 0

Answer:C

Explanation:

Partially submerged block along with vessel is accelerated upwards .

Initially the block weight is supported by buoyant force such that it is in equilibrium.

when the system start accelerating upwards then the effective gravity will be

g+a where a is the acceleration of the system.

so only net gravity is increased so block will not ascend or descend.

Mathematically

$F_b=weight$

$\rho _L\cdot V\cdot (g+a)=m(g+a)$

where $\rho _L=$ density of liquid

V=volume of object inside the water

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Which of Jafar's statements are correct regarding distance and displacement?

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Answer:The distance and magnitude of displacement are sometimes equal." Jafar is correct. The distance traveled and the magnitude of displacement are equal if and only if the path is a straight line in one direction.

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3 years ago

A gas in a closed container is heated with 12J of energy, causing the lid of the container to rise 3m with 5N of force. What is

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Answer:

27J

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Now the change in internal energy would be the sum of the received energy substended in the gas plus the work done by the system which is workdone that it will sustend in pushing the lid. This is expressed mathematically as;

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3 years ago

The interior space of large box is kept at 30 C. The walls of the box are 3 m high and have a ‘sandwich’ construction consisting

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Answer:

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exterior temperature, $T_o=0^{\circ}C$

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$\dot Q=\frac{dT}{(\frac{x}{kA}) }$

$\dot Q=\frac{dT}{R_{th} }$ ....................................(1)

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$R_{th}=\frac{1.4904}{A}$ .....................(2)

Putting the value from (2) into (1):

$\dot Q=\frac{30-0}{\frac{1.4904}{A} }$

$\dot Q=\frac{30\ A}{1.4904}$

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$20.129=0.04\times \frac{27.58-T_2}{0.05}$

$T_2=2.41875\ ^{\circ}C$

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