Question

1. When there is an imbalance in air pressure. will be needed to determine the speed of moving air.

a) Bernoulli's Principle

b) Archimedes' Principle

c) Charles' Law

d) Pascal's Principle

2 . You add ice ( 0° C) to iced tea (20°). What mass of ice is required to bring the temperature of 250 g of iced tea to 5° C ? Used iced tea = water = 4.190 kg-1 K-1 , water = 334 kJ kg-1

a) 44.3g

b) 114.6 g

c) 100 g

d) 300g

3. I decide to mix an ice cube into my hot tea . What happened ?

a) A phase change occurs , so we need to consider the heat of fusion for water.

b) No phase change occurs.

c) a phase change occurs , so we need to consider the heat of vaporization for water.

Answer #1

fast response needed
One liter of water at 54◦C is used to make iced tea. How much
ice at 0 ◦C must be added to lower the temperature of the tea to 12
◦C? The specific heat of water is 1 cal/g · ◦ C and latent heat of
ice is 79.7 cal/g. Answer in units of g.

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22oC and 1 atm. The average molar mass of air is 28.8
g/mol. Find the number of moles of air to fill the room
and the weight of the air in kg.
2) If it takes exactly 4 min. to completely melt a 2.0 kg block
of ice at 0.0° C, how much power is needed? (For water Lf
= 334 kJ/kg and...

A 1 m outer diameter spherical tank made of AISI 304 steel with
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and the mass rate (
m_dot) at which ice melts. Ignore convection effects of the melting
ice.
The latent heat of fusion of water at 0°C is 333.7 kJ/kg.
Thanks!

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The pressure in a liquid is:
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B)
linearly proportional to the depth
C)
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E)
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The reason for floating of some objects in water is due to:
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a) 6.9 °C
b) 1.7 °C
c) 0.04 °C
d) 5.4 °C
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