EXAMPLE Given: A sports car has a mass of 2 Mg and an engine efficiency of ɛ = 0.65. Moving forward, the wind creates a drag resistance on the car of F, = 1.2v2 N, where v is the velocity in m/s. The car accelerates at 5 m/s?, starting from rest. Find: The engine's input power when t = 4 s. Plan: 1) Draw a free body diagram of the car. 2) Apply the equation of motion and kinematic equations to find the car's velocity at t = 4 s. 3) Determine the power required for this motion. 4) Use the engine's efficiency to determine input power.

EXAMPLE Given: A sports car has a mass of 2 Mg and an engine efficiency of ɛ = 0.65. Moving forward, the wind creates a drag resistance on the car of F, = 1.2v2 N, where v is the velocity in m/s. The car accelerates at 5 m/s?, starting from rest. Find: The engine's input power when t = 4 s. Plan: 1) Draw a free body diagram of the car. 2) Apply the equation of motion and kinematic equations to find the car's velocity at t = 4 s. 3) Determine the power required for this motion. 4) Use the engine's efficiency to determine input power.

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 5.32P

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