PHY 1151 EXAM 1
50 g of ice at 0oC is added to 50 g of liquid water at 0oC in a well-insulated container, also at 0oC. After a while, the container will hold
50 g of ice, 50 g of liquid water.
1 mol of air has an initial temperature of 20oC. 200 J of heat energy are transferred to the air in an isochoric process, then 200 J are removed in an isobaric process. Afterward, the air temperature is
> 20 C
Water flows through a pipe having a varying width. More water flows per second through the wide section than through the narrow section because there is more room for it to flow
F
A gas in a container expands rapidly, pushing the piston out. The temperature of the gas
Falls.
"Tensile strain" is the applied force per cross-sectional area
False
A 50cm3 block of wood is floating partially submerged in water and a 50 cm3 block of iron is totally submerged in water. The block of wood has a greater buoyant force on it
False
As a solid melts, its temperature increases
False
If you double the pressure on the surface of a can of water, the buoyant force on a stone placed in that water will increase
Falsw
If the volume of a sealed container of gas is decreased, the gas temperature
Not enough information to tell.
In an isothermal expansion
Q>0
Heat is the energy that flows due to a temperature difference
T
Two identical cylinders, A and B, contain the same type of gas at the same pressure. Cylinder A has twice as much gas as cylinder B. Which is true?
TA<TB
Heat energy can be transferred from a cold reservoir to a hot reservoir only if an external agent does work on the system
True
The net change in thermal energy for a single cycle of a heat engine is always zero
True
In an isothermal expansion,
W<0 and Ws >0
A gas in a container expands rapidly, pushing the piston out. The temperature of the gas falls. This is because
Work is done
Dragging an object across a rough surface makes it warm, or even hot. The temperature increase occurs because of
Work.
When you blow some air above the upper face of a paper strip, the paper rises. This occurs because
the air above the upper face of the paper moves faster, which makes the pressure lower than at the lower face