• 100% Satisfaction Guarantee
Category: Homework
Satisfied Customers: 3040
Experience:  MIT Graduate (Math, Programming, Science, and Music)
3546829
Scott is online now

# I have some physics questions I need help with Please. Thank

### Customer Question

I have some physics questions I need help with Please. Thank you!!
#1 A bottle has a mass of 35.00g when empty and 98.44g when field with water. When filled with another fluid, the mass is 88.78g. What is the specific gravity of this other fluid?
#2 What is the difference in blood pressure (mm-Hg) between the top of the head and the bottom of a 1.60-m-tall person standing vertically?
#3
The maximum gauge pressure in a hydraulic lift is 18 atm. What is the largest size vehicle (kg) it can lift in the diameter of the output line is 22 cm?
#4
Water and oil are poured into a U shaped tube, open at both ends, and do NOT mix. They come to equilibrium. What is the density of ht oil? (HINT – Pressures at points a and b are equal. Why?)

#5. Determine the water gauge pressure at a house at the bottom of a hill fed by a full tank of water 5.0 m deep and connected to the house by a pipe that is 100 m long at an angle of 60 degrees from the horizontal. Neglect turbulence and frictional and viscous effects. How high would the water shoot if it came vertically out of a broken pipe in front of the house?
#6
A geologist finds that a moon rock whose mass is 8.20 kg has an apparent mass of 6.18 kg when submerged in water. What is the density of the rock?
#7
The specific gravity of ice is 0.917, whereas that for seawater is 1.025. What fraction of an iceberg is above the surface of the water?
#8
A 17-cm-radius air duct is used to replenish the air of a room 9.2 m X 5.0 m every 10 min. How fast does the air flow in the duct?
#9
A 5/8 – inch (inside) diameter garden hose is used to fill a round swimming pool 7.2 m in diameter. How long will it take to fill the pool to a depth of 1.5 m if water issues from the hose at a speed of 0.28 m/s?
#10 If wind blows at 30 m/s over your house, what is the net force on the flat roof if its area is 240 m2? (the 2 is squared)
#11 What is the lift (in newtons) due to Bernoulli’s principle on a wing of area 80 m2 (the 2 is squared) if the air passes over the top and bottom surfaces at speeds of 340 m/s and 290 m/s, respectively?
#12
Water at a pressure of 3.8 atm at street level flows into an office building at a speed of 0.60 m/s through a pipe 5.0 cm in diameter. The pipes taper down to 2.6 cm in diameter by the top floor, 20 m above. Calculate the flow velocity and the pressure in such a pipe on the top floor. Ignore viscosity. Pressures are gauge pressures.
YOU MUST SHOW WORK!!!!!!!!!!!!!!!!!!!!
Submitted: 7 years ago.
Category: Homework
Expert:  calcProf replied 7 years ago.
HiCustomer

Here are the answers to questions1, 5, 6, 7, 9, 10. Final answers are in bold font. For 4 and 8 some additional information is required. Please see notes below. I will get back to you with answers to 2, 3, 11, 12 shortly.

#1 A bottle has a mass of 35.00g when empty and 98.44g when field with water. When filled with another fluid, the mass is 88.78g. What is the specific gravity of this other fluid?

Mass of water in bottle when it is filled = 98.44 - 35.00 = 63.44 g
Density of water = 1 g/cm^3
Therefore volume of water in filled bottle = 63.44/1 = 64.33 cm^3
Volume of water and other fluid in filled bottle must be the same.
Therefore volume of other fluid in filled bottle is 64.33 cm^3.
Mass of other fluid in filled bottle = 88.78 - 35.00 = 53.78 g
Therefore density of other fluid = 53.78 / 64.33 = 0.836 g/cm^3

#2 What is the difference in blood pressure (mm-Hg) between the top of the head and the bottom of a 1.60-m-tall person standing vertically?

#3 The maximum gauge pressure in a hydraulic lift is 18 atm. What is the largest size vehicle (kg) it can lift in the diameter of the output line is 22 cm?

#4 Water and oil are poured into a U shaped tube, open at both ends, and do NOT mix. They come to equilibrium. What is the density of ht oil? (HINT – Pressures at points a and b are equal. Why?)

NOTE: Is there a diagram that goes with this?

#5. Determine the water gauge pressure at a house at the bottom of a hill fed by a full tank of water 5.0 m deep and connected to the house by a pipe that is 100 m long at an angle of 60 degrees from the horizontal. Neglect turbulence and frictional and viscous effects. How high would the water shoot if it came vertically out of a broken pipe in front of the house?

100 m long at 60 degree angle means a vertical height of 100 x sin(60 = 86.6 m
Total column height of water = 86.6 + 5 = 91.6 m (the extra 5 is from the depth of the the tank).
10 m of water = 1 atm
Therefore 91.6 m of water = 9.16 atm.
It would shoot up 86.6 m at the beginning.

#6 A geologist finds that a moon rock whose mass is 8.20 kg has an apparent mass of 6.18 kg when submerged in water. What is the density of the rock?

Loss of weight = mass of water displaced = 8.2 - 6.18 = 2.02 kg = 2020 g
Density of water = 1 g/cm^3
Therefore volume of water displaced = 2020 / 1 = 2020 cm^3
Therefore volume of moon rock = 2020 cm^3
Therefore density of moon rock = 8200 g / 2020 cm^3 = 4.059 g /cm^3

#7 The specific gravity of ice is 0.917, whereas that for seawater is 1.025. What fraction of an iceberg is above the surface of the water?

Let volume of iceberg be v cm^3
Denisty of iceberg = 0.917 g/cm^3
Therefore mass of iceberg = 0.917v grams
Since it is floating it has displaced 0.917v grams of sea water
Density of sea water = 1.025
Therefore volume of sea water displaced = 0.917v/1.025 cm^3
Fraction of iceberg submerged = volume of sea water displaced / volume of iceberg = 0.917 / 1.025 = 0.8946
Therefore fraction of iceberg above water = 1 - 0.8946 = 0.1054

#8 A 17-cm-radius air duct is used to replenish the air of a room 9.2 m X 5.0 m every 10 min. How fast does the air flow in the duct?

NOTE: another dimension of room is needed so that its volume can be calculated.

#9 A 5/8 – inch (inside) diameter garden hose is used to fill a round swimming pool 7.2 m in diameter. How long will it take to fill the pool to a depth of 1.5 m if water issues from the hose at a speed of 0.28 m/s?

Radius of pool = 7.2 / 2 = 3.6 m
Volume of water needed = π x 3.6 x 3.6 x 1.5 = 61.07 m^3

Radius of hose = 5/16 inch = 0.79375 cm = 0.0079375 m
Cross-sectional area of hose = π x 0.0079375 x 0.0079375 = 0.0001979 m^2
Flow of water = 0.28 m/s
Volume of water discharged per second = 0.0001979 x 0.28 = 0.00005542 m^3/s
Therefore time needed to fill pool = 61.07 / 0.00005542 =(NNN) NNN-NNNN28 sec = 12.75 days.

#10 If wind blows at 30 m/s over your house, what is the net force on the flat roof if its area is 240 m2? (the 2 is squared)

Lift = 0.5 x density x velocity^2 x area x Lift Coefficient
Air density = 1.2 kg/m3
Velocity = 30 m/s
Area = 240 m^2
Lift coefficient = 0.5
Therefore lift = 0.5 x 1.2 x 30^2 x 240 x 0.5 = 64800 N

#11 What is the lift (in newtons) due to Bernoulli’s principle on a wing of area 80 m2 (the 2 is squared) if the air passes over the top and bottom surfaces at speeds of 340 m/s and 290 m/s, respectively?

#12 Water at a pressure of 3.8 atm at street level flows into an office building at a speed of 0.60 m/s through a pipe 5.0 cm in diameter. The pipes taper down to 2.6 cm in diameter by the top floor, 20 m above. Calculate the flow velocity and the pressure in such a pipe on the top floor. Ignore viscosity. Pressures are gauge pressures.
Customer: replied 7 years ago.

Hi there!

Thank you for solving these for me. I am having a horrible time getting this concept down. There was not any illustrations given on the questions. That is why I am going crazy here :)

I thought there should be to solve them.

I wil have to ask tomorrow in class for validation purposes. You can skip those that should have illustrations.

THank you so much!!! You are the best!!!

Expert:  calcProf replied 7 years ago.
Thank you for your reply. I am sorry I could not respond last night. I'll finish up the remainder of the questions by this evening. If you need them done sooner than that please let me know. - calcProf.