Vault Of Euclid

Analyzing the Vertical Motion of a Ball

Rectilinear and curvilinear motion warmup

A ball is thrown vertically upward. Its height \( s \) (in feet) after \( t \) seconds is given by \( s = 40t - 16t^2 \). Find (a) when the ball hits the ground, (b) the instantaneous velocity at \( t=1 \), (c) the maximum height.
calculus-ikinematicsrectilinear-motionvelocityaccelerationmaximum-heightquadratic-functionderivativessecond-derivative-testcritical-pointsoptimizationpolynomial-differentiation

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What you need first

What this problem tests

Tests the ability to relate position, velocity, and acceleration, and to use derivatives to find maximum values.

This is a classic introductory calculus problem demonstrating the physical interpretation of the first and second derivatives in kinematics.

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