Uniform Acceleration: Solve for Initial Velocity

Thread starter davon806
Start date Oct 7, 2012
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Acceleration Uniform

AI Thread Summary

To solve for the initial velocity of a ball thrown upwards from a 30m cliff that hits the ground in 3.0 seconds, kinematic equations for uniformly accelerated motion can be applied. The relevant equation is s = ut + 0.5at², where s is the displacement, u is the initial velocity, a is the acceleration (which is -9.81 m/s² due to gravity), and t is the time. By substituting the known values into the equation, the initial velocity can be calculated. The problem emphasizes understanding the relationship between time, displacement, and initial velocity in uniformly accelerated motion. Ultimately, applying these concepts leads to determining the ball's initial velocity.

Oct 7, 2012

davon806

Homework Statement

Help please,I have no idea...This is the last question of my hw

A boy stands at the edge of a cliff which is 30m above the ground and throws a ball vertically upwards.It hits the ground 3.0s later.Find the initial velocity of the ball.

Homework Equations

The Attempt at a Solution

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Oct 7, 2012

lewando

Homework Helper

Gold Member

Can you think of any kinematic (constant acceleration) equations that might apply?

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