Bumpers on Cars Are Not of Much Use in a Collision

question 2

Multiple Choice

Bumpers on cars are not of much use in a collision. To see why, calculate the average force a bumper would have to exert if it brought a 1200-kg car (a so-called compact model) to a rest in 15 cm when the car had an initial speed of 2.0 m/s (about 4.5 mph) . (Bumpers are built with springs that compress to provide a stopping force without, hopefully, denting the metal.)

• A) 1.8 × 10⁴ N
• B) 1.6 × 10⁴ N
• C) 5.4 × 10⁴ N
• D) 6.5 × 10⁵ N
• E) 3.2 × 10⁴ N

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The amount of interest due per year as a percentage of the amount lent, deposited, or borrowed.

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The difference between total revenue and total costs, including both explicit and implicit costs.

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