Task 2.3 Explain the principle of conservation of energy and work-

energy transfer in dynamic systems

A) Provide a brief explanation of the principle of conservation of energy

B) Use an energy approach to obtain an estimate for

the force exerted on a 1250 kg vehicle that crashes

into a stationary rigid object at a speed of 70

kilometres per hour, assuming that the vehicle

compresses by approximately 400mm upon impact./nC)

A load of 250 kg is raised by a winch similar to that shown.

The winch has a winding drum of mass 52 kg, a diameter of 400

mm and radius of gyration 125 mm.

When the winch first starts, it lifts the load with an acceleration of

1 m/s² from rest through a distance of 3m. The winch system has

an overall friction torque of 1.3 kNm.

Calculate the following:

i)

v)

The final angular velocity of the drum

the angular acceleration of the drum

the work done by the driving motor

the input torque to the drum

the maximum power developed by the driving motor