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.)

Solutions

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.


Related Solutions

When traveling 40 mph (miles per hour), the distance that it takes Fred’s car to stop...
When traveling 40 mph (miles per hour), the distance that it takes Fred’s car to stop varies evenly between 120 and 155 feet. (This includes the reaction distance and the braking distance.) All of the questions are related to the stopping distance when Fred is traveling 40 mph. a) Let S be the distance it takes for Fred’s car to stop at when traveling 40 mph. Find the distribution, parameter(s), and support of S. b) What is the probability that...
1 design a column that supports 4500 lb if it is 12 feet long
1 design a column that supports 4500 lb if it is 12 feet long
5. A fluctuating external load of Ppeak = 4500 lb is applied at the bolted joint...
5. A fluctuating external load of Ppeak = 4500 lb is applied at the bolted joint given in Problem 4. (1) Find the factor nf of safety against the fatigue failure using the modified Goodman criterion. (2) Find the factor np of safety using the proof strength line. (3) Find the factor n0 of safety against joint separation. (4) Find the factor n of safety against yielding. (question 4 for reference) 4. For the assembly similar to the one in...
What is the speed in meters per second of a baseball traveling at 89 mph given...
What is the speed in meters per second of a baseball traveling at 89 mph given that 1 mph = 0.447 m/s?
The braking distance for a Krazy-Car traveling at 50 mph is normally distributed with a mean...
The braking distance for a Krazy-Car traveling at 50 mph is normally distributed with a mean of 50 ft. and a standard deviation of 5 ft. Answer the following without using the z table. a. What is the random variable in this problem? _______________________________ b. If top 3.5% of the cars are going too fast, what would be the braking distance? c. Find Q1, the median, Q3 and IQR. ________________________________
A 100kg mass traveling with a velocity of 15m/s on a horizontal surface strikes a spring...
A 100kg mass traveling with a velocity of 15m/s on a horizontal surface strikes a spring with a spring constant k = 5 N/m a. Find the compression of the spring required to stop the mass if the surface is frictionless b. Find the compression of the spring if the surface is rough (0.4ku=0)
A Honda N Box car is traveling on the highway at 70 mph (112.6 km/hr). It...
A Honda N Box car is traveling on the highway at 70 mph (112.6 km/hr). It is a nice summer day with no breeze and the temperature outside is 77F (25C, density = 1.184 kg/m^3, kinematic viscosity = 1.562*10^-5 m^2/s). The roof of the N Box car is 1478 mm wide and 3395 mm long. Determine how far above the car a bug must fly in order to NOT be affected by the passing car (unit: meters) **accurate to 3...
1a) Using radar, the police measured a 2670-lb car going 85.5 mph. Suppose that at the...
1a) Using radar, the police measured a 2670-lb car going 85.5 mph. Suppose that at the moment of the measurement the car\'s position was known to within 5.0 feet, what would the uncertainty be of the car\'s velocity? Again use the form of the uncertainty principle that has ≥ h / (4π ) 1b) If the car was in a 75 mph speed zone, could they get out the speeding ticket by using the uncertainty principle?
A highway being designed to AASHTO guidelines with a 70 mph design speed, and at one...
A highway being designed to AASHTO guidelines with a 70 mph design speed, and at one section, an equal tangent vertical curve must be designed to connect grades of +1% and -2%. If the grades intersect at station 100+00, determine the stationing of the PVC, PVT and curve high point for the minimum curve length based pn SSD requirements.
Ball A with a mass of 2.0 kilograms is traveling at 8.0 m/s strikes Ball B...
Ball A with a mass of 2.0 kilograms is traveling at 8.0 m/s strikes Ball B with a mass 5.0 kilograms which is at rest. After the collision, Ball A moves away at an angle of 40.0 degrees above the x-axis and Ball B moves away at an angle of -20.0 degrees below the x-axis. What are the final velocities of each ball? Draw and label a sketch of the problem.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT