Answer:
20cm
Explanation:
Hello!
remember that the condition for a body to be at rest is that the sum of its moments and its forces be zero,
To solve this problem you must draw the free body diagram of the stick (attached image) and sum up moments at point 0 (where the sharp is located), which results in the following equation
(100g)(40cm)=x(200g)

Answer:
D.) 1m/s
Explanation:
Assume the initial angle of the swing is 12.8 degree with respect to the vertical. We can calculate the vertical distance from this initial point to the lowest point by first calculate the vertical distance from this point the the pivot point:

where L is the pendulum length
The vertical distance from the lowest point to the pivot point
is the pendulum length 2m
this means the vertical distance from this initial point to the lowest point is simply:

As the pendulum travel (vertically) from the initial point to the bottom point, its potential energy is converted to kinetic energy:


where m is the mass of the pendulum, g = 10 m/s2 is the constant gravitational acceleration, h = 0.05 is the vertical it travels, v is the pendulum velocity at the bottom, which we are trying to solve for.
The m on both sides of the equation cancel out


so D is the correct answer
Steel is more elastic than rubber<span> because </span>steel<span> comes back to its original shape faster </span>than rubber<span> when the deforming forces are removed, hope it helps :)</span>