# SHM help?Watch

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#1
The question is: There are two forces acting on the pendulum bob shown in fig 4 explain how these forces are responsible for the resultant force F on the pendulum bob

I know the two forces are tension and weight, but I dont understand how weight can provide the centripetal force since its at a right angle to the motion? why isnt the only force tension

There is upward force on the bob due to the tension in the string and a
vertically downward weight of the bob.
These two forces add together to produce a resultant force to that is
horizontal and to the left as shown in

idk does shm include weight?
0
4 weeks ago
#2
The markscheme is correct.
There's no circular motion and no centripetal force.
Pendulum SHM is never actually straightforward, but we pretend the resultant force is proportional to distance from equil position and directed towards equil position, which is what is required for shm.
1
#3
thank you but how does the weight do to produce force f?
(Original post by old_teach)
The markscheme is correct.
There's no circular motion and no centripetal force.
Pendulum SHM is never actually straightforward, but we pretend the resultant force is proportional to distance from equil position and directed towards equil position, which is what is required for shm.
0
4 weeks ago
#4
If you draw a vector triangle, the resultant of the weight and the tension should be back towards the equil position.
0
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