Find how long does it take to hit the ground from a car off a cliff

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To determine how long it takes for a 500kg car to hit the ground after driving off a 400m cliff, the relevant equations of motion must be applied. The initial attempt incorrectly combined two separate questions, leading to confusion about the time of fall. The correct approach involves using the equation for free fall, which indicates that the time to fall can be calculated based on the height of the cliff and gravitational acceleration. The discussion highlights the importance of clearly defining the problem and using appropriate physics equations. Ultimately, the focus is on calculating the time it takes to fall 400m under gravity.
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Homework Statement


A 500kg car drives of a 400m cliff located on the surface of the Earth how long does it take to hit the ground

Homework Equations



F=ma
F=mg
d=1/d at^2

The Attempt at a Solution



i first did f=mg to find f
then i did f=ma converted that to find a
then did 1/2 at^2 converted that 2
d x 0.5 / 9.8 then i root it to find t
but i got the wrong answer, the answer is 9 seconds can some one tell me what i did wrong
 
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You're looking for an answer in metres, how far something is, is distance.

So the answer can't be 9 seconds. You already have how long it was in the air.
 
antphany said:
A 500kg car drives off a cliff at 50km/h how far would it land from the base of the cliff if it was in the air for 10 seconds


Homework Equations



F=ma
F=mg
d=1/d at^2
You are interested in its travel in the horizontal. The car experiences no acceleration horizontally.
 
NewtonianAlch said:
You're looking for an answer in metres, how far something is, is distance.

So the answer can't be 9 seconds. You already have how long it was in the air.

i been studying all night and its rly late i was combining 2 questions in 1 because i am soo tired i fixed the question now lol
 
antphany said:
A 500kg car drives of a 400m cliff located on the surface of the Earth how long does it take to hit the ground
This is an entirely different question, now. Your question has become: how long does it take something to fall 400 m, starting from rest.

What equation will you use for that?
 
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