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:
Torque is 93 Nm anticlockwise.
Explanation:
We have value of torque is cross product of position vector and force vector.
A force of 38 N, directed 30° above the x axis in the x-y plane.
Force, F = 38 cos 30 i + 38 sin 30 j = 32.91 i + 19 j
A particle is located on the x axis 4.9 m and we have to find torque about the origin on the particle.
Position vector, r = 4.9 i
Torque, T = r x F = 4.9 i x (32.91 i + 19 j) = 4.9 x 19 k = 93.1 k Nm
So Torque is 93 Nm anticlockwise.
Wavelength= velocity/frequency
5/2.5=2
Answer: E) A) salt water.
Explanation:
E) In equilibrium, pressure exerts equally in all directions, so for a given depth, the pressure is the same for all points located at the same depth, and it can be written as follows:
p = p₀ + ρ.g.h, where p₀ = atmospheric pressure, ρ=fluid density, h=depth from the surface.
A) The buoyant force, as discovered by Archimedes, is an upward force, that opposes to the weight of an object (as it is always downward), and is equal to the weight of the volume of the liquid that the object removes, which means that is proportional to the density of the liquid.
As salt water is denser than fresh water, the buoyant force exerted by the salt water is always greater than the one produced by the fresh water, so objects will float more easily in salt water than in fresh water.
In the limit, it is possible that one object float in salt water and sink in fresh water.
The answer for the cars speed is tue