Effort/ Load simple machines question

[IdleTorque]

Homework Statement

A screw jack that is used on cars whenever tyres are changed by the owner. The screw moves though a distance equal to its pitch whenever the effort lever ( jack handle) is given a complete turn. If the length of the jack handle is 24cm, the pitch is 2mm and the jack is required to lift a 900kg vheicle. Assuming efficiency is 100%. calculate the Effort reqired to lift the car.

Given Length of 24cm
Pitch of 2mm
Mass of 900kg
100% efficiency

Homework Equations

Velocity ratio
Mechanical advantage

The Attempt at a Solution

VR = 2
MA = L/E

900/2

450kg

 

[IdleTorque]

helppppp

 

[IdleTorque]

no help for this?

I've also assumed as the handle of 24cm goes around 1 complete turn, the jack goes up 2mm. Also gravity on the 900kg of the Load.

But its so confusing. And I'm new to physics can someone help me..