Ezy velocity questions Please help me im desperate

AI Thread Summary
To determine how long it takes for an object to fall from a height of 20 meters, the correct approach involves using kinematic equations, as the velocity of a freely falling body is not constant. The initial calculation of 2.04 seconds is incorrect; the time can be found using the equation t = √(2h/g), where h is the height and g is the acceleration due to gravity. For the second part, when an object is launched horizontally at 2 m/s from the same height, the horizontal distance it travels before hitting the ground can be calculated using the time of fall from part a. The discussion emphasizes the importance of applying the correct equations for uniformly accelerated motion. Understanding these principles is crucial for solving both parts of the problem accurately.
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Ezy velocity questions! Please help me // I am desperate!

Homework Statement



a)How long does it take an object to fall from a height of 20 m to reach the ground?

b)if an object is launched horizontally from a height of 20 m with a velocity of 2/m/s where will it hit the ground?

Homework Equations



we can use the velocity /a cceraltion forumulas

The Attempt at a Solution



is part a correct?? i think 20/ 9.8 m/s because its falling vertically which = 2.04 seconds

but part b I am not sure?
 
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The first part is wrong.

Write down the relevant equations.
 


rl.bhat said:
The first part is wrong.

Write down the relevant equations.

The relevant equation will be okay the equation for velocity

velocity= distance / time

we have been given the distance which is 20 m, and were trying to find time , ??
 


It is true only the velocity is uniform. In a freely falling body the velocity is not constant.
Go through the other kinematic equation for accelerating bodies.
 
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