GCSE Maths question, please help! exam tomorrow!?

Find an xpression for ' h ' in terms of ' v ' means dat ' h ' should be subject, or ' h ' should be on one side of da equation alone. U have done an xpression for ' v ' in terms of ' h ' , which is xactly da opposite of wat they have asked for.

h ∝ v²

h = kv²

Da constant in this equation is g, but since g is inversely proportional to h²,

h = (1/kg)v²

Where da value of g ≈ 10 m/s²

5 = (1/10k)(10)²

1/10k = 5/100

1/10k = 1/20

[ k = 2 ]

h = (1/kg)v²

h = (1/20)v²

[ h = v²/20 ]

Note that da xact value of g is 9.80665 m/s² , but for da sake of simpler calculations. 10 is a good enough aproximation

Hope this helps :)

Feel free 2 email me if u have any more questions !!

"... find an expression for h in terms of v ..."

"... My personal thought is that the answer is v= sq root of 20h ..."

You are giving an expression for v in terms of h.

What you need is:

h = v² / 2g < - - - - - h in terms of v (and g)

filling in the values for v and g:

h = 10² / 2×10

h = 100 / 20

h = 5

i basically had a ridicule maths exam and the pas sgrade replaced into rather low like ...30 or 40 % replaced right into a c which isnt even 1/2 so it wasnt too undesirable. yet i flow to a gramma college (regrettably) it honestly relies upon ont heschooli wager i dunnio x

I think you are not quite right.

E=1/2 mv^2=mgh

gh=1/2v^2

h=1/2 * (v^2)/g

if v=10 m/s, then h=1/2 *100/10=5m. ok.

You have done some good thinking but I am afraid you did a mistake.