Help With finding initial vertical speed

• mithilsheth
In summary, the conversation discusses how to calculate the initial vertical speed of a ball thrown upwards. The given information includes the acceleration of gravity, maximum height, and neglect of air resistance. The equation used is Vfinal squared = velocity initial squared + 2g times change in y, and after rearranging for the initial speed, the final answer is 11.9 m/s.
mithilsheth

Homework Statement

A Ball is thrown upwards. What is its initial vertical speed? The acceleration of gravity is 9.8 m/s2 and maximum height is 7.2 m ,. Neglect air resistance.

Homework Equations

Vfinal squared = velocity initial squared + 2g times change in y

The Attempt at a Solution

velocity final squared = velocity initial squared + 2 (-9.8)(7.2)
VF^2= VI^2 + -141.12
what now?/

What's the final velocity? (When it reaches the max height.)

the final velocity is not given. all that is given is v0, max height is 7.2 meters, and that the acceleration of gravity is 9.8 m/s/s/.

is the finaly velocity 0?

mithilsheth said:
is the finaly velocity 0?
Of course.

1 person
ohh ok... so would i use the same formula i used above to find the initial vertical speed?

what equation should i use to calculate the initial vertical speed?

mithilsheth said:
ohh ok... so would i use the same formula i used above to find the initial vertical speed?
Just use that equation you started with and solve for the initial speed.

how do i set it to be that velocity initial squared is on the left side of the equal sign, and velocity final squared is on on the right side?

mithilsheth said:
how do i set it to be that velocity initial squared is on the left side of the equal sign, and velocity final squared is on on the right side?
The final velocity is zero, so your equation becomes:

0 = Vi2 - 141.12

So how to get Vi2 alone? How can you get rid of that - 141.12?

you add 141.12 to the 0 and then find square root of 141.12?

mithilsheth said:
you add 141.12 to the 0 and then find square root of 141.12?
Sure! Basic algebra.

so the initial vertical speed would be 11.8793939239 m/s ?

mithilsheth said:
so the initial vertical speed would be 11.8793939239 m/s ?
Yes. But please round off to a reasonable number of significant figures. (2 or 3 is plenty.)

1 person
ok, i have one more question i need help with...

1. What is initial vertical speed?

Initial vertical speed, also known as initial velocity, is the speed at which an object is moving vertically at the beginning of its motion.

2. How is initial vertical speed calculated?

Initial vertical speed can be calculated by dividing the change in vertical distance by the change in time. This is represented by the formula: v = Δd/Δt, where v is the initial vertical speed, Δd is the change in vertical distance, and Δt is the change in time.

3. Why is it important to find the initial vertical speed?

Finding the initial vertical speed is important because it can help determine the trajectory and motion of an object. It is also a crucial component in calculating the total velocity and acceleration of the object.

4. What tools or techniques can be used to find the initial vertical speed?

There are several tools and techniques that can be used to find the initial vertical speed, such as using a stopwatch to measure time, a ruler to measure distance, and equations such as the kinematic equations and the equation for average velocity.

5. How does air resistance affect the initial vertical speed?

Air resistance can affect the initial vertical speed by slowing down the object's motion. This is because air resistance creates a force that opposes the motion of the object, causing it to decelerate. The amount of air resistance depends on the size, shape, and speed of the object.

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