# Who's dropping these balls?

Classical Mechanics Level pending

A ball at rest is dropped from the top of a building. It takes $$0.2 \text{ s}$$ to pass a window of height $$4.2 \text{ m}$$. How far is the top of the window from the top of the building?

Take $$g = 9.81 \text{ m/s}^2$$.

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