Question

52.
The drive shaft of an automobile rotates at 3600 rpm and transmits 80 hp from the engine to
the rear wheels. The torque developed by the engine is
A) 16.58 N-m B) 0.022 N-m C) 158.31 N N-m D) 1416 -Nm
​

Answer 1

Explanation:

Given The drive shaft of an automobile rotates at 3600 rpm and transmits 80 hp from the engine to  the rear wheels. The torque developed by the engine is

• We know that P = τω
• So torque τ = P / ω
• We know that 1 hp = 746 Watts
•               So 80 hp = 746 x 80
•                               = 59,680 Nms^-1
•         Now ω = 3600 rpm
•                      = 3600 / 60 x 2π rad / s
•                      = 120 π rad / S
•                     = 376.8 rad / S
• Now torque τ = 59680 / 376.8

Therefore torque τ = 158.31 N m