Find the initial velocity of a rocket given its total time of flight before returning to the ground.

Vault Of Euclid

Finding Initial Velocity from Time of Flight

Rectilinear and curvilinear motion warmup

A rocket was shot straight up from the ground. What must its initial velocity have been if it returned to earth in 20 seconds?

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What you need first

Basic algebra
Understanding of position functions in kinematics
Knowledge of the standard value of gravity in feet per second squared

What this problem tests

Tests the ability to set up and solve a kinematic equation for an unknown initial velocity given boundary conditions on position and time.

This is a standard introductory physics or calculus problem demonstrating the application of quadratic position functions to model motion under constant acceleration.

Finding Initial Velocity from Time of Flight

What you need first

What this problem tests

More on Rectilinear and curvilinear motion