The effort required to lift a load of 20 N using this lever would be 40 N.
Here's the explanation for finding the effort required to lift a load of 20 N using a lever with an effort arm of 4 m and a load arm of 8 m:
According to the principle of moments, the product of effort and effort arm must equal the product of load and load arm.
This principle states that the total turning force or moment about the fulcrum for both sides of the lever must be balanced.
Given:
Effort arm (d1) = 4 m
Load arm (d2) = 8 m
Load (W) = 20 N
To find the effort (E) required, we can set up the equation:
E × d1 = W × d2
Substituting the known values:
E × 4 = 20 × 8
Solving for E:
E = (20 × 8) / 4
E = 40 N .