Iron nail. the rest of those are not iron or some form of magnetic material.
Answer:
Explanation:
The first method to engage is to listen to where the sound of air in the inner Tor escaping originated and look to see if u can find it. You can then feel the escape air with your hand.
You can Put it inside a container of water and see the bubble and rotate the inner tube to pass all of it through the water
Hope this shows! It has all the equations for all of the problems u asked in the comments
Answer:
66 rpm
Explanation:
The period of oscillation is given by
where T is time period of oscillation which is given as 0.35 s, k s spring constant and m is the mass of the object attached to the spring.
Also, net force is given by
Net force=
where 
is the elongation, L is original length, 
is the angular velocity
Substituting the equation of 
into the above we obtain
