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# suvat questions help!! watch

1. I can't rearrange equations and am really struggling with physics particularly with suvat questions!
Please could someone explain how you would arrange:
a) s= 1/2(v+u) x t, to find t
b) v^2 = u^2 + 2as, to find u

and I think that's it thank youuu
2. (Original post by mandms300)
I can't rearrange equations and am really struggling with physics particularly with suvat questions!
Please could someone explain how you would arrange:
a) s= 1/2(v+u) x t, to find t
b) v^2 = u^2 + 2as, to find u

and I think that's it thank youuu
you probably want to revise your maths notes on algebra... and get proficient at rearranging or you'll have a tough time in physics exams.

algebra literally means 'balance' and if it helps you could think about an old two pan balance.

the equal sign means the pointer is exactly in the middle and so whatever is in the left pan weighs exactly the same as whatever is in the right pan.
if you double the weight on the left pan AND double the weight on the right pan they will still have the same weight on each pan... if you subtract the same amount of weight from both pans they will have the same weight and this also applies to squaring or taking roots.
if x=y
it means x+7=y+7
and 3x=3y
and x^2=y^2
and sqrt(x)=sqrt(y)

the rule is that you are allowed to do the same 'thing' on both sides of the equals sign... and you need to come up with a sequence of things that gets the variable you need separated out on one side of the equals sign and everything else on the other side.

simple example

x=2y
*divide both sides of the equals sign by 2*
x/2=y
----
a=b+c
*subtract c from both sides of the equals sign*
a-c=b
----

s=1/2(v+u) t
*multiply both sides by 2*
2s=(v+u)t
*divide both sides by (v+u)*
2s/(v+u)=t

----
v^2=u^2+2as
*subtract (2as) from both sides of the equals sign*
v^2 -2as = u^2
*take square root of both sides of the equal sign*
sqrt(v^2 -2as) = u
3. (Original post by Joinedup)
you probably want to revise your maths notes on algebra... and get proficient at rearranging or you'll have a tough time in physics exams.

algebra literally means 'balance' and if it helps you could think about an old two pan balance.

the equal sign means the pointer is exactly in the middle and so whatever is in the left pan weighs exactly the same as whatever is in the right pan.
if you double the weight on the left pan AND double the weight on the right pan they will still have the same weight on each pan... if you subtract the same amount of weight from both pans they will have the same weight and this also applies to squaring or taking roots.
if x=y
it means x+7=y+7
and 3x=3y
and x^2=y^2
and sqrt(x)=sqrt(y)

the rule is that you are allowed to do the same 'thing' on both sides of the equals sign... and you need to come up with a sequence of things that gets the variable you need separated out on one side of the equals sign and everything else on the other side.

simple example

x=2y
*divide both sides of the equals sign by 2*
x/2=y
----
a=b+c
*subtract c from both sides of the equals sign*
a-c=b
----

s=1/2(v+u) t
*multiply both sides by 2*
2s=(v+u)t
*divide both sides by (v+u)*
2s/(v+u)=t

----
v^2=u^2+2as
*subtract (2as) from both sides of the equals sign*
v^2 -2as = u^2
*take square root of both sides of the equal sign*
sqrt(v^2 -2as) = u
Thank you so much! This really helped me understand thank you!!

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