Which one of the following sketches correctly describes a lever of sec

Which one of the following sketches correctly describes a lever of second class ?

Sketch (a) showing Fulcrum at one end, Load in the middle, Effort at the other end.
Sketch (b) showing Fulcrum at one end, Effort in the middle, Load at the other end.
Sketch (c) showing Fulcrum in the middle, Load at one end, Effort at the other end.
Sketch (d) showing Fulcrum at one end, Load in the middle, Effort at the other end.
This question was previously asked in
UPSC NDA-2 – 2024
Assuming Sketch (a) shows the configuration with the Fulcrum at one end, the Load in the middle, and the Effort at the other end, it correctly describes a lever of the second class.
– Levers are simple machines consisting of a rigid bar that pivots around a fixed point called the fulcrum. Forces are applied to the lever: the effort (the force applied by the user) and the load (the force exerted by the object being moved or worked on).
– Levers are classified into three classes based on the relative positions of the fulcrum (F), the load (L), and the effort (E).
– Class 1 Lever: F is between E and L (E – F – L or L – F – E). Examples: seesaw, crowbar.
– Class 2 Lever: L is between F and E (F – L – E). Examples: wheelbarrow, nutcracker, bottle opener.
– Class 3 Lever: E is between F and L (F – E – L). Examples: tweezers, fishing rod, forearm lifting a weight.
– The question asks for a second-class lever. In a second-class lever, the Load is always located between the Fulcrum and the Effort.
– Option A’s description (“Fulcrum at one end, Load in the middle, Effort at the other end”) matches the configuration of a Class 2 lever (F – L – E).
– Option B describes a Class 3 lever (F – E – L).
– Option C describes a Class 1 lever (E – F – L or L – F – E, specifically F in the middle).
– Option D’s description is identical to Option A’s. Without seeing the sketches, we rely on the description provided in the options. Assuming Sketch (a) corresponds to the description in A and is a visual representation of F-L-E, then A is correct.
Second-class levers always provide a mechanical advantage greater than 1 (MA > 1), meaning the effort required is less than the load force, because the effort arm (distance from fulcrum to effort) is always longer than the load arm (distance from fulcrum to load).
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