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2 years ago

14

A downhill skier reaches the steepest part of a trail. Her speed increases from 9 m/s to 18 m/s in 3 seconds. What is her averag

e acceleration

1 answer:

Cerrena [4.2K]2 years ago

8 0

Answer:

3m/s²

Explanation:

final velocity - initial velocity

______________________ = Acceleration

elapsed time

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The following table lists the work functions of a few common metals, measured in electron volts. Metal Φ(eV) Cesium 1.9 Potassiu

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$\lambda=510 nm=5.1\cdot 10^{-7} m$

So its energy is

$E=\frac{hc}{\lambda}=\frac{(6.63\cdot 10^{-34}Js)(3\cdot 10^8 m/s)}{5.1\cdot 10^{-7} m}=3.9\cdot 10^{-19}J$

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So, if the same light shine on sodium, then the maximum kinetic energy of the emitted electrons will be

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3 years ago