Free Falling Object: Calc. d = 19.6m in 1s

AI Thread Summary
The discussion revolves around calculating the distance a free-falling object travels in one second, starting from rest. Using the formula d = v1t + 1/2at^2, the calculated distance for the first second is 4.9 meters, leading to a total distance of 19.6 meters when multiplied by four. A participant expresses doubt, citing a classmate's answer of 274 meters, which is deemed incorrect as it would imply an unrealistic fall of 68.5 meters in the first second. The consensus is that the original calculation is logical and accurate. The conversation emphasizes the importance of correctly applying physics principles to solve motion problems.
Mid
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Homework Statement
A free falling object starts from rest and travels a quarter of its full distance in one second. solve for how far the object falls in total?
Relevant Equations
gravity (9.8 m/s), motion formulas
v1 = 0 m/s
a = 9.8 m/s
t = 1sec
d = ?

d = v1t + 1/2at^2
d = 4.9 m
total distance = 4.9*4
= 19.6 m
thats what i was doing but i think I am wrong
 
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Hello @Mid,

Welcome to PF! :welcome:

Mid said:
Homework Statement: A free falling object starts from rest and travels a quarter of its full distance in one second. solve for how far the object falls in total?
Homework Equations: gravity (9.8 m/s), motion formulas

v1 = 0 m/s
a = 9.8 m/s
t = 1sec
d = ?

d = v1t + 1/2at^2
d = 4.9 m
total distance = 4.9*4
= 19.6 m
I'll agree with that. :smile:

thats what i was doing but i think I am wrong
What makes you think you're wrong?
 
collinsmark said:
Hello @Mid,

Welcome to PF! :welcome:I'll agree with that. :smile:What makes you think you're wrong?
I'm in grade 12 and this question was directly taken from 1st year university physics and my teacher said the answer isn't that simple to get and students in my class got the answer to be around 274 m
 
Mid said:
I'm in grade 12 and this question was directly taken from 1st year university physics and my teacher said the answer isn't that simple to get and students in my class got the answer to be around 274 m
The answer is quite simple if you approach the problem logically, as you have done.

274m cannot possible be correct, as the object would have to fall 68.5m in the first second.
 
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