Direct proportion question
Maths and statistics discussion, revision, exam and homework help.
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Direct proportion questionA ball falls vertically after being dropped. The ball falls a distance, d metres, in a time of t seconds.
d is directly proportional to the square of t.
I worked out the first question which was the formula:
Another question was, calculate the time the ball takes to fall 605m
So i did
That was the final answer, however i was wondering, do i not divide by 5 to get t on its own?
If not for this one, do i ever? Or do you leave a number next to it always?
Thank you!
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Re: Direct proportion question(Original post by TenOfThem)
did you not divide by 5 to get from 605 to 121
Aaah right yeh! So it would just be
then Sqrt that? :O? -
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Re: Direct proportion question(Original post by DeathByBSOD)
My Maths is kinda rusty, :s but where did you get the 5 FROM?
so i think its:
Therefore,
the 5 is from the first part of the question, when 20 is directly proportion to 4k so k=5 -
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Re: Direct proportion question(Original post by IgorYakov)
the 5 is from the first part of the question, when 20 is directly proportion to 4k so k=5
Ah Ok thanks.
