Question

In: Mechanical Engineering

A 4500 lb SUV is traveling at 65 mph when it strikes a staged attenuator designed...

A 4500 lb SUV is traveling at 65 mph when it strikes a staged attenuator designed to produce three different energy dissipation rates. For the first 6 ft, the attenuator produces a force of 20,000 lb on the impacting vehicle. The second stage is 4 ft long and produces a deceleration force of 40,000 lb. “How long does the attenuator’s 3rd stage have to be to safely stop the SUV if its deceleration force is 60,000 lb. Construct the a-s, a-t, and v-t curves for this impact. (Hint: safely stopping the SUV means the vehicle stops before using up the 3rd stage.)

Expert Solution

Mass of the SUV = 4500 lb

Initial velocity = 65 mph = 95.30 ft/s

Take first stage data

Take data for 2 stage

Take data for 3 stage

The graph of acceleration and time is given below.

The graph of acceleration and distance is given below.

The graph of velocity and time is given below.

samet mamat answered 2 years ago

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