Concept explainers
(a)
The friction force exerted by the road.
(a)
Answer to Problem 40P
The friction force exerted by the road is
Explanation of Solution
Write the expression for drag force on the car.
Here,
Frictional force and drag force are opposite in direction.
Using Newton’s second law, write the expression for net force in the horizontal direction.
Here,
Solve equation (III) for
Use equation (I) in (II).
Conclusion:
Substitute,
Substitute,
Therefore, the friction force exerted by the road is
(b)
The acceleration of the car if drag coefficient is
(b)
Answer to Problem 40P
The acceleration of the car if drag coefficient is
Explanation of Solution
Conclusion:
Substitute,
Therefore, the acceleration of the car is
(c)
The possible maximum speed pf the car at
(c)
Answer to Problem 40P
The possible maximum speed pf the car at
Explanation of Solution
At the maximum speed, the net force along the horizontal direction is zero.
Conclusion:
Substitute,
Therefore, The possible maximum speed pf the car at
(d)
The possible maximum speed pf the car at
(d)
Answer to Problem 40P
The possible maximum speed pf the car at
Explanation of Solution
Conclusion:
Substitute,
The drag reduction significantly affects maximum speed.
Therefore, the possible maximum speed pf the car at
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Chapter 5 Solutions
Principles of Physics: A Calculus-Based Text
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- A worker develops a tension T in the cable as he attempts to move the 41-kg cart up the 19° incline. Determine the resulting acceleration a of the cart if (a) T = 120 N and (b) T = 158 N. Neglect all friction, except that at the worker's feet. The acceleration a is positive if up the slope, negative if down the slope. 41 kg 12° m/s² m/s² 19° Answers: (a) T = 120 N, a= i (b) T=158 N, a = Telarrow_forwardThe 200-kg glider B is being towed by airplane A, which is flying horizontally with a constant speed of v = 194 km/h. The tow cable has a lengthr = 59 m and may be assumed to form a straight line. The glider is gaining altitude and when e reaches 16, the angle is increasing at the constant rate ở = 3 deg/s. At the same time the tension in the tow cable is 1550 N for this position. Calculate the aerodynamic lift Land drag D acting on the glider. Assume o = 12°. B A Part 1 Calculate the magnitude of the acceleration of glider B. Answer: a = i m/s2 Save for Later Attempts: 0 of 1 used Submit Answerarrow_forwardTo maintain a constant speed, the force provided by a car's engine must equal the drag force plus the force of friction of the road (the rolling resistance). The density of air is 1.2 kg/m. (a) What are the drag forces in newtons at 75 km/h and 104 km/h for a Toyota Camry? (Drag area = 0.70 m? and drag coefficient = 0.28.) at 75 km/h at 104 km/h (b) What are the drag forces in newtons at 75 km/h and at 104 km/h for a Hummer H2? (Drag area = 2.44 m2 and drag coefficient = 0.57.) at 75 km/h at 104 km/h N Additional Materialsarrow_forward
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- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning