**In the soapbox Derby, young participants build non-motorized cars with very low friction wheels. Cars race by rolling down a hill. The track at Akron’s Derby Downs, where the national championship is held, begins with 55-ft long section tilted 13° below horizontal.**

**a) What is the maximum possible acceleration of a car moving down this stretch of track? **

F_{net}= F_{gravity}

=> a_{max} = m_{gravity} x sin(13)

=>a_{max} = 9.8 x 0.22

= 2.20 m/sec^{2}

**b) If a car starts from rest and undergoes this acceleration for the full l, what is its final speed in m/s?**

55 feet converted to meters =** 16.76** meters

v^{2} = u^{2} + 2as

=>v^{2} = 0 + 2 x 2.20 x 16.76

=>v = √ (73.74)

= 8.59 m/s

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