Equation problem.

[Gareth56]

Can someone please explain how the answer h is arrived at because it appears on both sides of the equation?

t1 = 0.69s & t2 = 2.37s

h =((h+0.5gt1^2)t1)t2 - 0.5gt2^2

The answer is h = 8.02m

I tried attaching small scan of the equation from the book but despite the file size only being 12KB the system rejected it :(

[KatieB]

What was the book and page number. I may have it?

I find it difficult to understand your equation but normally you would bring terms containing the subject h to one side of the equation.

factorise that side contining h
i.e. h(........)=b say
so h= b/(........)

Hope that helps

[Gareth56]

I tried to attach a 12KB file to make it easier to see the equation but I got the message "UPLOAD ERROR" that it exceed my quota by 8.4 KB. Does anyone know what this means because according to the instructions I can attach a JPG file up to ~39KB

Does this make any more sense?

t1 = 0.69s & t2 = 2.37s g =9.81m/s

h =(h+0.5gt1^2)/t1)t2 - 0.5gt2^2

The answer is h = 8.02m

[talkingturtles]

t1 = 0.69s & t2 = 2.37s g =9.81m/s

h =(h+0.5gt1^2)/t1)t2 - 0.5gt2^2

Firstly put the values you have for t1, t2, and g into your eqution:

h=((h+ 0.5x9.81x0.69)/0.69)x2.37 - 0.5x9.81x2.37

Expand the sets of brackets:

h=(h/0.69 + 0.5x9.81x0.69/0.69)x2.37 - 0.5x9.81x2.37

h=(2.37h)/0.69 + 0.5x9.81x0.69x2.37 - 0.5x9.81x2.37

Put the numbers into a calculator:

h=(2.37h)/0.69 + 8.0211465 - 27.5508945

h=(2.37h)/0.69 - 19.529748

multiply by 0.69:

0.69h=2.37h - 13.47552612

subtract 0.69h from each side:

0 = 1.68h - 13.47552612

divide by 1.68:

0 = h - 8.0211465

subtract 8.0211465 from each side:

h=8.02 (3sig fig)

and theres your answer!

Hopethat helps you work through it. <3