EE003-4-0-ESC
Engineering Science
Tutorial 3: Fluids
1. A 10-kg baby sits on a three-legged stool. The diameter of each of the stool’s round feet
is 2.0 cm. A 60-kg adult sits on a four-legged chair that has four circular feet, each with a
diameter of 6.0 cm. Who applies the greater pressure to the floor and by how much?
2. In a hydraulic lift, the radius of the pistons are 2.50 cm and 10.0 cm. A car weighing W =
10 kN is to be lifted by the force of the large piston.
(a) What is the force FA which must be applied to the small piston?
(b) When the small piston is pushed in by 10.0 cm, how far is the car lifted?
(c) Find the mechanical advantage of the lift, which is the ratio W/FA.
3. A hydraulic lift is lifting a car that weighs 12 kN. The area of the piston supporting the
car is A, the area of the other piston is a, and the ratio A/a is 100.0. How far must the
small piston be pushed down to raise the car a distance of 1.0 cm?
4. In the Netherlands, a dike holds back the sea from a town below sea level. The dike
springs a leak 3.0 m below the water surface. If the area of the hole in the dike is 1.0
cm2, what force must the Dutch boy exert to save the town?
5. When a mercury manometer is connected to gas main, the mercury stands 40.0 cm
higher in the tube that is open to the air than in the tube connected to the gas main. A
barometer at the same location reads 74.0 cm Hg. Determine the absolute pressure of
the gas in cm Hg.
6.
A small statue in the shape of a falcon has a weight of 24.1 N. The owner of the statue
claims it is made of solid gold. When the statue is completely submerged in a container
brimful of water, the weight of the water that spills over the top and into a bucket is
1.25 N. Find the specific gravity and density of the metal. Is the density consistent with
the claim that the falcon is solid gold?
7.
A nozzle of inner radius 1.00 mm is connected to a hose of inner radius 8.00 mm. The
nozzle shoots out water moving at 25.0 m/s.
(a) At what speed is the water in the hose moving?
(b) What is the volume flow rate?
(c) What is the mass flow rate?
8.
Plumbum has a weight of 142.0 N. The object is suspended from a scale and hung so
that is completely submerged in water (but not touching bottom). The scale reads
129.4N. Find the specific gravity of the object.
Asia Pacific University of Technology and Innovation
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