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learner

Hey people..

Here are my shortcuts in mechanics.. not shortcuts actually, just formulae worth remembering, which make it faster to solve sums. They can all be derived quite easily.

I?ve done it myself, so there may be a better way of putting something. If there is, do let me know.

1) If 3 masses on a smooth horizontal table are connected using strings as shown, common acc. = F1/(m1+m2+m3)

2) In the following diagram,

a = F / (m1+m2+m3)

Force on m1= F=F1..say

Force on m2= (m2+m3)F1 / (m1+m2+m3)

Force on m3= m3F1/(m1+m2+m3)

3) For a person of mass m climbing up a rope with acceleration a, T=m(g+a)

If he goes down with same acceleration, T=m(g-a)

MORE INTERESTING

4) In the given figure,

T1 = F + (m1+m2)g

T2 = F + m2g

5) T = m1m2g /(m1+ m2)

a = m2g /(m1+m2)

6) Acc= F/(m1+m2+m3)

T1 = (m2 + m3)F/(m1+m2+m3)

T2 = m3F/(m1+m2+m3)

7) If there is no friction:

aA = F/ m

aB = 0

In case of friction, if F< umg??u is coeff. of friction

aA = aB = F/(M+m)

If F>umg

aA = (F-umg)/m

aB= umg/M

8) If there is no friction:

aA = 0

aB = F/M

In case of friction, if F< umg??u is coeff. of friction

aA = aB = F/(M+m)

Force on A = mF/(m+M)

If F>umg,

aA = ug

aB= (F-umg)/M

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Ones with pulleys and inclined planes coming soon..

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I'm sorry, I'm unable to put diagrams with text...so you'll have to keep referring to them below...

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HOPE YOU FOUND SOME OF THIS USEFUL..

PLEASE LEAVE COMMENTS AND POINT OUT MISTAKES IF ANY..

RATE IF IT HELPED!!!

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