Explanation

Cold working strengthens metals by plastic deformation below their recrystallization temperature.

It increases hardness and tensile strength but reduces ductility.

Explanation

Shafts can be made by turning/grinding, hot rolling, or cold drawing depending on size and strength requirements.

All these methods are commonly used in industry for shaft manufacturing.

Explanation

Washers are standardized based on the diameter of the hole to fit specific bolts or screws.

Other dimensions like thickness and outside diameter vary, but the hole size is primary for specification.

Explanation

Factor of Safety (FoS) measures how much stronger a system is than required for normal use.

It is calculated as FoS = Yield Stress / Working Stress, ensuring safety under loads.

Explanation

Chisels require high hardness and wear resistance to cut hard materials.

High carbon steel provides the required hardness after heat treatment.

Explanation

Carburizing is applied to low-carbon steel (about 0.1%–0.2% carbon).

The process increases surface carbon content to improve hardness and wear resistance.

Explanation

Die casting produces gears with good surface finish but lower strength.

Therefore, such gears are generally used for light-duty applications, not heavy load transmission.

Explanation

A suddenly applied load produces double the stress compared to the same load applied gradually.

This is due to the absence of gradual energy distribution in sudden loading.

Explanation

In simple harmonic motion, acceleration is directly proportional to displacement and always directed toward the mean position.

The ratio a/x remains constant and equal -w², which defines SHM.

Explanation

Bauxite is the most important ore of aluminum which contains only 30–54% alumina.

The rest is a mixture of silica, various iron oxides,

and titanium dioxide along with trace amounts of zinc, phosphorous, nickel, vanadium etc.