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# M1 Pulleys watch

1. 7). Two particles P and Q of masses 7kg and 2kg respectively are connected by a light inextensible string. Particle P rests on a smooth table. The string passes over a smooth pulley fixed at the edge of the table and Q is hanging freely. The system is released from rest. Find the acceleration of P.

Not sure what to do, I tried using F=ma:

The actual answer is 2.18 ms-2. What have I done wrong?
2. usually g has the value 9.8
3. (Original post by ViralRiver)
7). Two particles P and Q of masses 7kg and 2kg respectively are connected by a light inextensible string. Particle P rests on a smooth table. The string passes over a smooth pulley fixed at the edge of the table and Q is hanging freely. The system is released from rest. Find the acceleration of P.

Not sure what to do, I tried using F=ma:

The actual answer is 2.18 ms-2. What have I done wrong?
If take so

-2
4. Yes, I know that.

EDIT: Oh I see what I did. I somehow couldn't read my calculator properly >.< xD .

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