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

here we know that ball will drop down by total distance 3.2 m

so here we know that

now using kinematics

now in the same time it will cover horizontal distance of 0.75 m

so speed of the ball will be

i believe the answer would be:

d. violin, clarinet, french horn, and tuba