Assume that a 4.00 kg pendulum bob is hanging from a 7.90 m long cable. the cable is attached to a hook in the ceiling 10 m up from the floor. (a) if a person releases the bob, from the small angle approximation, how long will it take the bob to swing back to him? s (b) what is meant by the small angle approximation? any angle less than 3° any angle less than 5° any angle less than 10° any angle less than 15°

Explanation:

Given

mass of Pendulum m=4 kg

Length of cable= 7.90 m

Distance between roof and Floor=10 m

will Provide Torque

thus

where I=moment of inertia

=angular acceleration

here is small therefore \sin \theta \approx \theta

thus

And

Small angle refers to any angle where

i.e. any angle less than

r=rho l/a where a is the area, l is the length and rho is resistivity so the greater the area the lesser the resistance thats why the earth pin is thicker bcos current follow the shortest path, so less resistive .

sleep paralysis is a parasomnia, events associated with sleep.

sleep paralysis happens when you are in the middle of waking up or falling asleep. it is the feeling of being conscious but unable to move. it definitely involves hallucinations.

i had a friend that had sleep paralysis and he told me a story one time where he was laying in bed and he couldn't move his body no matter how hard he tried and there was someone standing in the corner of his room coming towards him. he couldn't move and you can't "wake up" because you are already conscious. sometimes sleep paralysis can be triggered by frequent waking up during the night based off of multiple trips to the bathroom, or if you had ever been abused, sleep paralysis can start happening from things like that.