ENGINEERING FUNDAMENTALS
6th Edition
ISBN: 9781337705011
Author: MOAVENI
Publisher: CENGAGE L
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Chapter 7, Problem 21P
To determine
Determine the frontal area of the car.
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Students have asked these similar questions
The air resistance to the motion of a vehicle
is something important that engineers
investigate. As you may also know, the
drag force acting on a car is determined
experimentally by placing the car in a wind
tunnel. For a given car, the experimental
data is generally represented by a single
coefficient that is called the drag coefficient.
It is given by the relationship:
Fa
C, =
where
C, = drag coefficient
F, = measured drag force (Ib)
p = air density (slugs/ft')
V = air speed inside the wind tunnel (ft/s)
A = frontal area of the car (ft²)
What is the appropriate unit for C, if the
preceding equation is to be homogeneous in
units? Show all steps of your work.
3. The drag force of an object moving through a fluid is found to be FD = CpAv² where Cis
the drag coefficient, A is the area of the object facing the fluid, and p is the density of the
fluid. The drag coefficient is determined experimentally. Using this form of the drag force,
calculate the terminal velocity of a 75 kg skydiver in 2 positions: diving head first like an
arrow (C=0.70, A=0.18 m²) and laying horizontal (C=1.0, A=2 m²). The density of air is
p = 1.21 kg/m³.
DYNAMICS OF RIGID BODIES
Two masses of 14 kg and 7 kg connected
by a flexible inextensible cord rest on a
smooth plane inclined 45° with the
horizontal as shown in the figure. When
the masses are released, what will be the
tension T in the cord? Assume the
coefficient of friction between the plane
and the 14-kg mass is 1/4 and between
the plane and the 7-kg mass is 3/8?
7 kg
14 kg
450
Chapter 7 Solutions
ENGINEERING FUNDAMENTALS
Ch. 7.2 - Prob. 1BYGCh. 7.2 - Prob. 2BYGCh. 7.2 - Prob. 3BYGCh. 7.2 - Prob. 4BYGCh. 7.2 - Prob. 5BYGCh. 7.2 - What does strain represent?Ch. 7.2 - Prob. BYGVCh. 7.5 - Prob. 1BYGCh. 7.5 - Describe two different methods that you can use to...Ch. 7.5 - Prob. 3BYG
Ch. 7.5 - Prob. 4BYGCh. 7.5 - Prob. 5BYGCh. 7.5 - Prob. BYGVCh. 7 - Prob. 1PCh. 7 - Prob. 2PCh. 7 - Prob. 3PCh. 7 - Prob. 4PCh. 7 - Prob. 5PCh. 7 - Prob. 6PCh. 7 - Prob. 7PCh. 7 - Prob. 8PCh. 7 - Prob. 9PCh. 7 - Prob. 10PCh. 7 - Investigate the diameter of the electrical wire...Ch. 7 - Prob. 12PCh. 7 - Prob. 13PCh. 7 - Prob. 15PCh. 7 - Prob. 17PCh. 7 - Using area as your variable, suggest ways to cool...Ch. 7 - Prob. 19PCh. 7 - Prob. 20PCh. 7 - Prob. 21PCh. 7 - Prob. 22PCh. 7 - Prob. 23PCh. 7 - Prob. 24PCh. 7 - Prob. 25PCh. 7 - Prob. 26PCh. 7 - Prob. 27PCh. 7 - Prob. 28PCh. 7 - Prob. 30PCh. 7 - Prob. 31PCh. 7 - Prob. 32PCh. 7 - Prob. 33PCh. 7 - Prob. 34PCh. 7 - Prob. 35PCh. 7 - Prob. 36PCh. 7 - Prob. 37PCh. 7 - Prob. 38PCh. 7 - Prob. 39PCh. 7 - Prob. 40PCh. 7 - Prob. 41PCh. 7 - Prob. 42PCh. 7 - A 10 cm long rectangular bar (when subjected to a...Ch. 7 - Prob. 44PCh. 7 - Prob. 45PCh. 7 - Prob. 46PCh. 7 - Prob. 47PCh. 7 - Prob. 48PCh. 7 - Prob. 49PCh. 7 - Prob. 50P
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- The air resistance to the motion of a vehicle is something important that engineers investigate. As you may also know, the drag force acting on a car is determined experiementally by placing the car in a wind tunnel. For a given car, the experimental data is generally represented by a single coefficient that is called the drag coefficient. It is given by the relationship C(4)=F(d)/ 1/2 pV^2 (A) C(d)= drag coefficient F(d)= measured drag force (lb) p= air density (slugs/ft^3) V= air speed inside the wind tunnel (ft/s) A=frontal area of the car (ft^2) What is the appropiate unit for C, if the proceeding equation is to be homogeneous in units? show all steps of your workarrow_forwardd) The viscosity of a fluid is to be measured using a viscometer constructed of two 750 mm long concentric cylinders. The outer diameter of the inner cylinder is 150 mm and the gap between the two cylinders is 1.2 mm. The inner cylinder is rotated at 200 rpm and the torque is measured to be 10 Nm. a) Derive a generals expression for the viscosity of a fluid using this type of viscometer, and; b) Determine the viscosity of the fluid for the experiment above. Shaft е -Cylinder - Velocity Profilearrow_forward14.11. As we explained in Chapter 7, the air resistance to motion of a vehicle is something important that engineers investigate. As you may also know, the drag force acting on a car is determined experimentally by placing the car in a wind tunnel. The air speed inside the tunnel is changed, and the drag force acting on the car is measured. For a given car, the experimental data is generally represented by a single coefficient that is called drag coefficient. It is defined by the following relationship: Fa Cả where Ca = drag coefficient (unitless) Fa = measured drag force (N or 1b) p= air density (kg/m³ or slugs/ft') V = air speed inside the wind tunnel (m/s or ft/s) A = frontal area of the car (m? or ft') The frontal area A represents the frontal projection of the car's area and could be approximated simply by multiplying 0.85 times the width and the height of a rectangle that outlines the front of a car. This is the area that you see when you view the car from a direction normal to…arrow_forward
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