Which would have the lowest input force?

A short lever with a large fulcrum

A long lever with the fulcrum as far as possible from the load

A Short lever with the fulcrum as close as possible to the load

A long lever with the fulcrum as close as possible to the load

A long lever with the fulcrum as close as possible to the load

Explanation:

If F be the effort, W be the weight, L₁ be the distance of load from fulcrum and L₂ be the distance of effort from the fulcrum,

Taking moment of force about the fulcrum, we have

W x L₁ = F x L₂

F = W x (L₁ / L₂)

F will be minimum when L₁ will be minimum.

Hence fulcrum should be as close as possible to the load.