Tag: terms related to machines

$\eta=\frac{M.A}{V.R}=\frac{l}{h(l/h)}=1$
$M.A=\frac{l}{h}, V.R=\frac{l}{h}$

An inclined plane is a sloping surface that behaves like a simple machine whose mechanical advantage is always greater than $1$.

The vertical force is the gravitational force means weight of the load. 

Mechanical advantage is the ratio of the load lifted to the effort applied. It is expressed as load divided by effort.

A crowbar is a classic example of a first-class lever, where the fulcrum is between the effort and the load. Therefore, stating it is a second-class lever is incorrect.

Mechanical advantage is the amplification in force due to the use of a machine . The mechanical advantage of wheel and axle is given by 

Efficiency is the (often measurable) ability to avoid wasting materials, energy, efforts, money, and time in doing something or in producing a desired result. In a more general sense, it is the ability to do things well, successfully, and without waste. In more mathematical or scientific terms, it is a measure of the extent to which input is well used for an intended task or function (output).

A wheelbarrow is example 3 class third lever rest all are example of simple machine. hence option D is incorrect

C lever. The edge of the can serves as the fulcrum and the lid is the load.

The velocity ratio is define as $VR=\dfrac{{Effort}{} _{distance}}{{load}{} _{distance}}$
hence option A is correct.