# Physics

## Steam is leaving a 4-L pressure cooker whose operating pressure is 150 kPa

Question: Steam is leaving a 4-L pressure cooker whose operating pressure is 150 kPa. It observed that the amount of liquid in the cooker has decreased by 0.6 L in 40 min after the steady operating conditions are established, and the cross-sectional area of the exit opening is 8mm2. Determinea)The mass flow rate of the …

## A sculptor and his assistant are carrying a wedge-shaped marble slab up a flight of stairs, as shown in the figure

Question: A sculptor and his assistant are carrying a wedge-shaped marble slab up a flight of stairs, as shown in the figure. The density of the marble is uniform. Both are lifting straight up as they hold the slab completely stationary for a moment. Does the sculptor have to exert more force than the assistant …

## An object is placed 20.0 cm from a converging lens with focal length 15.0 cm (see the figure, not drawn to scale)

Question: An object is placed 20.0 cm from a converging lens with focal length 15.0 cm (see the figure, not drawn to scale). A concave mirror with focal length 10.0 cm is located 75.0 cm to the right of the lens, (a) Describe the final image—is it real or virtual? Upright or inverted? (b) What …

## If 2.0 mol of nitrogen gas (N2) are placed in a cubic box, 25 cm on each side

Question: If 2.0 mol of nitrogen gas (N2) are placed in a cubic box, 25 cm on each side, at 1.6 atm of pressure, what is the rms speed of the nitrogen molecules? Answer:

## Bryce Canyon National Park, shown in the accompanying photo, is in dry southern Utah

Question: Bryce Canyon National Park, shown in the accompanying photo, is in dry southern Utah. It is carved into the eastern edge of the Paunsaugunt Plateau. Erosion has sculpted the colorful limestone into bizarre shapes, including spires called “hoodoos.” As you and a companion (who has not studied geology) are viewing the scenery in Bryce …

## Larger animals have sturdier bones than smaller animals

Question: Larger animals have sturdier bones than smaller animals. A mouse’s skeleton is only a few percent of its body weight, compared to 16% for an elephant. To see why this must be so, recall, that the stress on the femur for a man standing on one leg is 1.4% of the bone’s tensile strength. …

## What mass of ice at -10.2°C is needed to cool…

Question: What mass of ice at -10.2°C is needed to cool a whale’s water tank, holding 1.09 103 m3 of water, from 20.0°C down to a more comfortable 10.0°C? Answer: 1.09 X 103 m3 = 1.09 x 106 kg of water. specific heat of water C = 4.187 kJ / kg latent heat of fusion = 334 kJ/kg …

## You have a lens of focal length 15cm…

Question: You have a lens of focal length 15cm. Draw array diagram showing the image created for and object 2 cm tall placed 30 cm to the left of the lens from part a. State whether the image is real and whether it is inverted. a) Calculate the location of the image and the magnification …

## An automobile engine slows down from 4500rpm…

Question: “an automobile engine slows down from 4500rpm to 1200rpm in2.5seconds..Calculate..A) Angular Acceleration assumed constant, andB) The total number of revolutions the engine makes in this time” Answer: Î±=(Ï‰2-Ï‰o2)/t, so first convert the rpm’s torad/s then you get 472.5rad/s and 126rad/s andthe acceleration is -138.6rad/s2. The total revolutions that are made areÎ”Î¸=1/2Î”Ï‰t=748rads, so748rads/2Ï€=1.2x102revolutions