Mechanical Engineering Review Online

1. An automobile has a 1,200kg mass and is accelerated to 7 m/s². Determine the force required to perform acceleration. (Ans: 8,400N) 

2. A spring is compressed by 0.05 in for every 1 lb_f of applied force. Determine the deflection of the same spring when the applied force is 6.5 lb_m. Let g_o =32.0 ft/sec². (Ans. 0.3230 in) 

3. A new temperature scale is desired with freezing of water at 0^oX and boiling point at atmospheric pressure occurring at 1000^oX. Derive a conversion between degrees Celsius and degrees X. What is the absolute zero in degrees X? (Ans. -2,731.5^oX) 

4. A pump discharges into a 3m per side cubical tank. The flow rate is 300 L/min and the fluid has a density of 1.2 times that of water (density of water = 1000 kg/m³). Determine:
a.The flowrate in kg/
b.The time it takes to fill the tank. (Ans. 6 kg/s, 90 min) 

5. An aluminum sphere with a mass of 0.35 g has a radius of 0.50 cm. Determine if the aluminum is solid or has a hollow space inside it? If it has a hollow space, how much is missing from it? 
Aluminum = 2,700 kg/m³. (Ans. the sphere is hollow, 1.0637 g)

6. Air contained in a rigid container has a pressure of -0.5 bar. If the atmospheric pressure is 740 mm Hg, and the density of mercury is 13.59 g/cm3, determine the absolute pressure of the container, in bar. (Ans. P_abs = 48.6552 kPa)

7. Considering the Figure shown below, determine the absolute pressure of tank A and tank B. Let SGHG = 13.6 (Ans. 321.0248 kPa_abs)

8. A pressure gauge shown in the figure below is connected to a closed container at a gage pressure of 45 kPa. If the spring scale is k = 55 N/m and the area of the piston is 0.70 cm², determine how far will the spring be compressed if the portion containing the spring is (a) vacuum (b) open to the atmosphere at 100 kPa. (Ans. 5.727 cm)