The problem states that a car traveling at 100km/h has acollision and in order f

Question

The problem states that a car traveling at 100km/h has acollision and in order for survival deceleration cannot exceed30g's. (1g=9.8m/s). assuming uniform decelartion ofthis value calculate the distance oner which the front end of thecar must be designed to collapse if a crash brings the car to astop. Question- Where does the 5/18 m/s come from?                       The problem states that a car traveling at 100km/h has acollision and in order for survival deceleration cannot exceed30g's. (1g=9.8m/s). assuming uniform decelartion ofthis value calculate the distance oner which the front end of thecar must be designed to collapse if a crash brings the car to astop. Question- Where does the 5/18 m/s come from?                      

Explanation / Answer

well lets see, force cant be greater than 30g's =30x9.81=294.3m/s2so now its a velocity problem v1=100km/h / 3.6 = 27.778m/s, v2=0, a=-294.3, d=? v22=v12+2ad (equation for motion) (0m/s)2=(27.778m/s)2+ 2 x(-294.3m/s2) * d 0=771.617 + 2 x -294.3 x d d=1.311m 5/18 m/s = 1 km/h message me if you want a proof of the last equality NOTE ON POS VS NEG ACCELERATION* in this equation we are using the forward direction as positive,the opposite direction is negative in this question, when the car hits the wall, it slows down, henceit is accelerating in the opposite direction of the motion. Since the car is slowing down, it has a negative acceleration

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.