The efficient of a single fixed pulley is 80% find its mechanical advantage
ideally 1
If the single pulley moved with the target it would be two. However a single pulley attached to the wall gains you nothing but perhaps a better pulling angle. so 0.8 *1 = 0.8
Now if the pulley is on the wall and you sit on top of the pile of bricks on the sled you are pulling, then you get MA = 2, ( the wall pulls on both you and the sled) but you did not say that.
To find the mechanical advantage of a single fixed pulley, we need to understand the concept of mechanical advantage.
Mechanical advantage is the measure of the effectiveness of a machine in multiplying the force or effort applied to it. In the case of a pulley, it is the ratio of the output force to the input force.
In the scenario given, the efficiency of the fixed pulley is provided as 80%. Efficiency is the measure of how much useful work an object or system produces compared to the energy it receives as input. It is expressed as a percentage.
The formula for efficiency is:
Efficiency = (Useful output energy / Input energy) * 100
Since we know the efficiency is 80%, we can rewrite the equation as:
80 = (Useful output energy / Input energy) * 100
Now, let's focus on the mechanical advantage. The mechanical advantage of a single fixed pulley is always 1 because it does not multiply the input force. It only changes the direction of the applied force. So, the mechanical advantage in this case is 1.
To summarize, the mechanical advantage of a single fixed pulley is always 1, regardless of its efficiency.