Question

A lever of length 2 m is used to lift 800 N by the application of 300 N effort. If the distance ofthe load from the fulcrum is 0.5 m load and effort are at the ends of the lever, calculate:

(a) Mechanical advantage
(b) Velocity ratio
(c) Efficiency​

Answer 1

Mechanical advantage is calculated as 2.67, the velocity ratio is 3, and the efficiency of the lever is 89%.

Step-by-step explanation:

The student's question involves the use of a lever to lift a load and asks for the calculation of mechanical advantage, velocity ratio, and efficiency of the lever.

Mechanical advantage (MA) is the ratio of the load lifted to the effort applied. In this case, MA = Load/Effort = 800 N / 300 N = 2.67.

The velocity ratio (VR) of a lever is the ratio of the distance moved by the effort to the distance moved by the load. Since the effort and load are at the ends of a 2-meter long lever and the load is 0.5 meters from the fulcrum, the effort arm is 1.5 meters long (2 m - 0.5 m). VR = Effort Distance/Load Distance = 1.5 m / 0.5 m = 3.

Efficiency is the ratio of the mechanical advantage to the velocity ratio, multiplied by 100 to get a percentage. Efficiency = (MA/VR) × 100 = (2.67/3) × 100 = 89%.