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A cyclist is traveling at 7m s¹, then accelerates at 2.5m s2 for 15 seconds.

a.
How far did they travel during this time
What was the final speed after 15 seconds?
b.

User Veda
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1 Answer

3 votes

Answer:

a)


{ \tt{s = ut + (1)/(2) {at}^(2) }} \\ \\ { \tt{s = (7 * 15) + (1)/(2) * 2.5 * {15}^(2) }} \\ \\ { \tt{s = 105 + 281.25}} \\ { \tt{s = 386.25 \: m}}

b)


{ \tt{v {}^(2) = {u}^(2) + 2as}} \\{ \tt{ {v}^(2) = {7}^(2) + (2 * 2.5 * 386.25)}} \\ { \tt{ {v}^(2) = 1980.25}} \\ { \tt{v = 44.5 \: m}}

User Plugie
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