In a real system of levers, wheel or pulleys, the AMA (actual mechanical advantage) is less than the IMA (ideal mechanical advantage) because of the presence of friction.
In fact, the IMA and the AMA of a machine are defined as the ratio between the output force (the load) and the input force (the effort):

however, the difference is that the IMA does not take into account the presence of frictions, while the AMA does. As a result, the output force in the AMA is less than the output force in the IMA (because some energy is dissipated due to friction), and the AMA is less than the IMA.
Answer:
22J
Explanation:
Given :
radius 'r'= 3cm
rotational inertia 'I'=4.5 x
kgm²
mass on one side of rope '
'= 2kg
mass on other side of rope'
' =4kg
velocity'v' of mass
' = 2m/s
Angular velocity of the pulley is given by
ω = v /r => 2/ 3x 
ω = 66.67 rad/s
For the rotating body, we have
KE =
I ω²

= 10J
Next is to calculate kinetic energy of the blocks :

=12J
Therefore, the total kinetic energy will be
KE =
=10 + 12
KE= 22J
Note that this is a position vs time graph.
From A to B, the graph is a straight line with a nonzero slope. This indicates a constant velocity.
From B to C, the graph is a straight line with 0 slope. This indicates a constant position, i.e. the object remains stationary.
From C to D, the graph is a straight line with a nonzero slope. This indicates a constant velocity.
<span>A design is remodeled after analysis and tested again.</span>
Answer:
1kg
Explanation:
this box is the smallest and weighs the least. Hope this helps :]