A skateboarder starting from rest accelerates down a ramp at 2 m/s for 2 s. What is the final speed of the skateboarder

Initial speed of the skateboard (u) = 0 m/s (Starts from rest)

Acceleration of the skateboard (a) = 2 m/s²

Time taken by the skateboard (t) = 2s

By using equation of motion, we get:

Final speed of the skateboard(v) = 4 m/s

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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