A 1300 kg four-wheel-drive car moves down the highway at a constant speed. Due to air drag, there is a 200 N force attempting to slow the vehicle down. However, the engine applies a constant moment (we say torque in the automotive industry) on the wheels to keep the vehicle moving. The tires have a radius of 25 cm, and the bearing in the wheel has a radius of 2.5 cm with a coefficient of friction of 0.10. Assume all wheels behave identically. a) Approximately how much moment is lost due to friction? b) How much torque is required to keep the vehicle moving? c) How might you reduce the losses in the system?

A 1300 kg four-wheel-drive car moves down the highway at a constant speed. Due to air drag, there is a 200 N force attempting to slow the vehicle down. However, the engine applies a constant moment (we say torque in the automotive industry) on the wheels to keep the vehicle moving. The tires have a radius of 25 cm, and the bearing in the wheel has a radius of 2.5 cm with a coefficient of friction of 0.10. Assume all wheels behave identically. a) Approximately how much moment is lost due to friction? b) How much torque is required to keep the vehicle moving? c) How might you reduce the losses in the system?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.31P

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