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M3 Elastic Strings Question Help

Can someone help me answer the following question:

A particle P of mass 2kg is attached to the mid-point of a light elastic string of natural length 2m and modulus of elasticity 20N. One end of the string is attached to point A of a ceiling and the other end is attached to point B on the floor 3m vertically below A. Calculate the tension in AP and the tension in PB.

Thanks

Reply 1

Zacken

Original post by Student 977

Can someone help me answer the following question

Sure. What thoughts of your own do you have? What have you already tried? What specific issue are you having?

Reply 2

Student 977

Thanks for the reply.

I understand that from Hooke's law, the total tension in the string is 10N, but I am unsure of where to go from there.

Reply 3

Zacken

Original post by Student 977

Thanks for the reply.

I understand that from Hooke's law, the total tension in the string is 10N, but I am unsure of where to go from there.

Why don't you draw a sketch? Label the tensions in AP to be T_1 and the tension in BP to be T2.

Now resolve up and down. You have T_1 - T_2 = 2g.

The net tension in each part of the string, T=10N

For the top half T1-2g=10 (i) and for the bottom T2+2g=10 (ii)

Can you take it from here?