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A 1300-kg car coasts on a horizontal road, with a speed of18m/s. After crossing an unpaved sandy stretch of road 30.0 mlong, its speed decreases to 15

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asked 2021-03-24
A 1300-kg car coasts on a horizontal road, with a speed of18m/s. After crossing an unpaved sandy stretch of road 30.0 mlong, its speed decreases to 15m/s. If the sandy portion ofthe road had been only 15.0 m long, would the car's speed havedecreasedby 1.5 m/s, more than 1.5 m/s, or less than 1.5m/s?Explain. Calculate the change in speed in that case.

Answers (1)

2021-03-26
\(\displaystyle{v}^{{{2}}}={u}^{{{2}}}-{2}{a}{s}\);find a puttings=30;u=18;v=15
\(\displaystyle{v}'^{{{2}}}={u}^{{{2}}}-{2}{a}{\left({15}\right)}\)
Now comparev with v'
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