if for a force of 0.5 N we have a displacement of -0.02m we can calculate the elastic constant(k) with the formula F=-kx(F=0.5N x=-0.02)
k=F/x k=0.5/0.02=25N/m
now we can calculate the period by the formula
T=2π√(m/k)
in the mass we convert grams to kilograms so 100g=0.1kg
T=6.28√(0.1/25)⇒T=0.39seconds
The nail has become a temporary magnet, while the
bar magnet remains a permanent magnet.
Answer:

Explanation:
From the question we are told that
Velocity if travel 
Diameter of prototype
and 
Scale ratio=
Generally Velocity of of the model using Froud's model is mathematically given as





Answer:
a ) 2.368 rad/s
b) 3.617 rad/s
Explanation:
the minimum angular velocity that Prof. Stefanovic needs to spin the bucket for the water not to fall out can be determined by applying force equation in a circular path
i.e
------ equation (1)
where;


Also

since; that is the initial minimum angular velocity to keep the water in the bucket
Now; we can rewrite our equation as :

So; Given that:
The rope that is attached to the bucket is lm long and his arm is 75 cm long.
we have our radius r = 1 m + 75 cm
= ( 1 + 0.75 ) m
= 1.75 m
g = acceleration due to gravity = 9.81 m/s²
Replacing our values into equation (2) ; we have:

b) if he detaches the rope and spins the bucket by holding it with his hand ; then the radius = 0.75 m
∴

Answer:
4
Explanation:
friction
weight
normal reaction
force to overcome inertia