You are Here: Home >< Physics

# I need help urgently... Please!! watch

1. this a very hard physics question got me, i'm stucked! Please guide me

Take g = 10 m/s2 in this question.) The ends of a light inextensible string, of length 0.7 m, are attached to two fixed points A and B at the same horizontal level, where AQ = 0.4 m and QB = 0.1 m. A particle of mass 0.2 kg is attached to the string at the point P, where AP = PB = 0.3 m. The particle hangs in equilibrium, with the string passing over a small smooth peg fixed at the point Q in the horizontal line between A and B at a distance of 0.1 m from B, as shown below. Give three reasons why the tensions in the three parts, AP, PQ, and QB, of the string have the same value, and find this value. Also, determine the angle between QA and the force exerted on the string by the peg. Refer figure below:

http://s919.photobucket.com/albums/a...t=DSC01488.jpg

The peg is now removed and a particle of mass m kg is attached to the string at the midpoint M of PB. The system hangs in equilibrium with PM horizontal, and AP and MB inclined to the horizontal at angles β and γ respectively, where cos β = 7/9 and cos γ = 1/3, as shown in the figure below. Calculate m

http://s919.photobucket.com/albums/a...t=DSC01486.jpg

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: February 8, 2010
Today on TSR

### Uni league tables

Do they actually matter?

### University open days

• University of Warwick
Sat, 20 Oct '18
• University of Sheffield
Sat, 20 Oct '18
• Edge Hill University
Faculty of Health and Social Care Undergraduate
Sat, 20 Oct '18
Poll

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE