The maximum torque produced by the engine of the car occurs at 4750 rpm, when th

Question

The maximum torque produced by the engine of the car occurs at 4750 rpm, when the engine is generating 286 HP. The designer followed the following method and chosen steel shaft having yield stress at 80,000 psi and a factor of safety = 4. (Although the shaft is rotating, assume the maximum shear stress can be adequately approximated by assuming the material in equilibrium.)

If we choose a hollow shaft instead of a solid shaft, assuming that for good stability, one require the wall thickness of the hollow shaft should be 30% of its outer radius such that t(solid) = t(allow). With this setting, the expression for inner radius R(i) and outer radius R(o)

(a) R(i) = 0.3 R(o)
(b) R(i) = 0.7 R(o)
(c) R(i) = 0.3 R(o) / 0.7
(d) R(i) = 0.3 / 0.7 R(o)

Explanation / Answer

t = Ro*.3

Ri= Ro-t

Ri= Ro-0.3Ro

Ri= 0.7Ro

so b part is correct answer

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.