Atmospheric, Gauge and Absolute Pressure

1. When measuring gauge pressure with an open tube manometer a difference of 17 cm Hg height was registered. Recall that the value of the atmospheric pressure was made in Guadalajara 81.13 kPa, what is the value of the absolute pressure in

a) cm de Hg,
b) Pa
c) kPa
d) mm de Hg,
e) N/m²
f) m de Hg
g) lb/in²

2. What is the reading of a manometer if inside a tank there is an absolute pressure of 104kPa and an atmospheric pressure of one atmosphere?

3 Determine the depth of a submarine is the ocean If the hydrostatic pressure is 11 x 10⁶ Pa. Considering that the water it is in has a density of 1.025 g/cm³

Archimedes's and Pascal's Principles

1. A force of 600 N is applied to the small piston of a hydraulic press which area is 12 cm². What must be the diameter of the large piston if it is applied a force of 8 400N?

2. A cube of 9 cm on each side weighs 50.36 N. What is the mass and the material that it is made up of when it is submerged in alcohol (790 kg/m³)?                    

3. What volume will 400 g of alcohol occupy? What is the weight and weight density of this volume if the density of the alcohol is 0.79 g/cm³?

4 Calculate the force to be applied on an area of 10 cm², to produce a pressure of 500 N/m²?

5. A 50 mL test tube is filled with mercury up to a height of 37 cm. Determine the hydrostatic pressure at the bottom and the force being exerted there if the inner radius of the test tube is 1.46 cm. The density of mercury is 13 600 kg/m³

6. Calculate the diameter of the small piston of a hydraulic press that produces a force of 600 N, and the large piston, which diameter is 50 cm, occurs a force of magnitude equal to 5 600 N.

7. A cube of aluminum weighs 0.20 N in the air, if its density is 2.9 g/cm³. What is its apparent weight if it is submerged in a liquid which density is 1.35 g/cm³?

8. An iron cube of 17.5 cm on each side is submerged into water. If it weighs 56 N in air, what is its weight in water?

9. An irregular piece of metal has a weight of 1.544 kg. When it is submerged completely in water, it weighs 14.3472 N. Determine the density of the object and the kind of material it is made of.

10. It was observed that the mass of a fragment of a rock is 9.17 g in the air. When the piece is immersed in a fluid of 873 Kg/m³ of density, its apparent mass is only 7.26 g. What is the density of the rock?

11. A solid object weighs 8 N in the air, when this object is hung from a spring scale and it is submerged into water, its apparent weight is only 6.5 N. What is the density of the object?

Venturi's and Pitot's tubes

1. In the wide part of a Venturi tube, there is a diameter of 68 cm and a pressure of 350 kPa. In the narrowing of the tube the diameter is reduced to the half and there is a pressure of 92 000 N/m².

a) What is the speed of the water flowing through the pipe?

b) What is the rate of flow?

2. The wide part of a Venturi tube has a diameter of 6 inches (1 in= 2.54 cm) and a pressure of 150 kPa. In the section that connects to a pipe, the diameter is reduced to one-third and a pressure of 135.06 mm Hg is recorded.

a) What is the speed of the gasoline (ρ = 700 kg/m³) flowing through the pipe?

b) What is the rate of flow?

3. A 0.0275 cm² crack is made by a stone in a water tank. Determine the speed and the amount of water in liters that escapes in 20 minutes from the crack if the water tank is 1.8 m above.

4. Calculate the time in minutes that it will take to fill a pool which capacity is 7000 liters if the rate of flow is 30 x 10³ cm³/s.

5. A water tank is 16 cm above the faucet. Determine the speed of the water when the faucet is completely open and the time needed to fill a 12-liter bucket. Consider that the faucet has an output area of 2.85 x10 ^{– 4} m²

6. The pipe of a building, on the ground floor, carries water at a speed of 5 m/s and a gauge pressure of 375kPa,What is the speed of the moving water in the pipe 2.8 m above if the gauge pressure is 362 475Pa?

Density, Weight Density and Volume

1. The perchloroethylene is used to clean clothes in laundries. Calculate the volume in liters that can be hold in 500 kg and help Pedro Gómez to decide if he accepts or not the 900 kg. Consider that the container can hold 1000 liters and the weight density of the cleaning fluid of 15 892 N/m³

2. Calculate the density of earth assuming that is a sphere which diameter is 12742 km and 5.976 x 10 ²⁴ kg of mass. Note: The volume of a sphere is V= (4/3) π r³

3. Determine the weight density of a substance which mass is 800 kg and a volume of 250 liters.

4. What is the mass and weight of 10 liters of mercury?

5. A 250-mL flask is filled with an unknown liquid. An electronic balance indicates that the liquid has a mass of 220g. What is the density and the weight density of the liquid?

 

Linear, Surface and Cubic Expansion

1. A material with a volume of 100 cm³ at 10 °C is heated to 35 °C and it suffers an increase in 0.455 cm³. Determine the material and the volumetric expansion coefficient.

2. A Pyrex flask has an initial volume of 600 ml at 20 °C. At what temperature will the volume of the flask be 603 ml?

3. A bronze rod has 2.00 m in length to 15°C. What temperature must the rod be heated to have a new length of 2.01 m?

4. A circular hole in a plate of steel has a diameter of 20.0 cm at 27 ° C. At what temperature will it be heated to have an area of 314 cm²?

5. A steel measuring tape is used to measure the length of a rod of copper of 98 cm when it is at 10 ºC which is the temperature of the measuring instrument calibration. What is the reading in the measuring tape of the length of the rod of copper when the temperature is 32 ºC?

Specific Heat Capacity and Thermal Equilibrium

1. A 1200 g aluminum block is heated at 235 °C and placed in a partially filled container with 3.5 kg of water at 20 °C. What will the final temperature be?

2. Determine the specific heat of a metallic sample of 100 g which requires 1557.2 J to raise its temperature from 50 to 90 ° C. Also, indicate what material the sample is made up of ___________

3. 800 g of lead, are at a temperature of 15 °C. What will its final temperature be if 12,761J were supplied?

Coulomb's Law

1 Calculate the distance in centimeters in which two electric charges of 7 mC and 3 mC are rejected with a force of 5.47 N. Besides calculate the value of the electric force if they were in oil.

2. A charge of 5µC is in the air to 20 cm of another charge of – 2 µC. What is the value of the force exerted by the charges? What would the value of the force if they were submerged in water?

3. An electric charge of – 3µC is in the air to another charge to 12 mm. The value of the force with which are rejected is 750 N. What is the value of the unknown charge?