Question

The average velocity of the vehicle is 180 km/hr. It requires 2000 W for operation of

30 min. Find the magnitude of constant tractive effort.

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Answer 1

The average velocity of the vehicle is 180 km/hr. It requires 2000 W for operation of  30 min.

Given,

Power required by the vehicle P = 2000 Nm/s

Average velocity of the vehicle V = 180/3.6 = 50 m/s

∆t = 30 × 60 = 1800 s

The work of tractive force

W = P × ∆t ..........(1)

= (2 × 10³) × (1.8 × 10³)

= 3.6 × 10^6 Nm

The tractive effort's magnitude |F| =?

W = F × ∆s = |F| × |v| × ∆t ..........(2)

The magnitude of the tractive effort ,

combining equations (1) and (2), we take,

|F| = ( P × ∆t ) / (|v| × ∆t) = [ 3.6 × (10^6) ] / 50 N = 72 kN

The magnitude of constant tractive effort is 72 kN