ANS:E - 2124

2^nd term = (1^st term) x 1 + 1 = 15 x 1 + 1 = 16. 3^rd term = (2^nd term) x 2 + 2 = 16 x 2 + 2 = 34. 4^th term = (3^th term) x 3 + 3 = 34 x 3 + 3 = 105. 5^th term = (4^th term) x 4 + 4 = 105 x 4 + 4 = 424 6^th term = (5^th term) x 5 + 5 = 424 x 5 + 5 = 2125  6^th term should 2125 instead of 2124.

ANS:D - hostile

No answer description is available. 

ANS:B - No

No, the header files have any kind of extension.

ANS:E - All the above.

Wrought iron corrodes easily than steel. Cast iron has highest resistance to corrosion followed by steel and then wrought iron.

ANS:B - 10°

Loss angle δ = 90 - 80 = 10°.

ANS:D - all (a), (b) and (c)

The Fenske-Underwood equation used for calculating the minimum number of theoretical plates in a distillation column is valid for constant relative volatility. The Fenske-Underwood equation is a fundamental equation in distillation design and analysis. It is used to calculate the minimum number of theoretical plates required for a given separation, based on the relative volatility (𝛼α) of the components being separated. The equation is: 𝑁min=log⁡(𝛼min)log⁡(𝛼min−1𝑅min)Nmin​=log(Rmin​αmin​−1​)log(αmin​)​ Where:

• 𝑁minNmin​ is the minimum number of theoretical plates required.
• 𝛼minαmin​ is the minimum relative volatility required for the separation.
• 𝑅minRmin​ is the minimum reflux ratio required for the separation.

ANS:A - < 1

In the context of liquid metals, the ratio of hydrodynamic boundary layer thickness (δh\delta_{\text{h}}δh​) to thermal boundary layer thickness (δt\delta_{\text{t}}δt​) is generally greater than 1.

Explanation:

1. Boundary Layer Thickness:
   • Hydrodynamic Boundary Layer Thickness (δh\delta_{\text{h}}δh​): This refers to the distance from the solid surface where the velocity of the fluid reaches approximately 99% of the free-stream velocity. It characterizes the thickness of the layer where viscous effects dominate.
   • Thermal Boundary Layer Thickness (δt\delta_{\text{t}}δt​): This refers to the distance from the solid surface where the temperature of the fluid reaches approximately 99% of the bulk temperature. It characterizes the thickness of the layer where thermal diffusion dominates.
2. Liquid Metals:
   • Liquid metals typically have high thermal conductivity and low viscosity compared to other liquids.
   • Due to their high thermal conductivity, the thermal boundary layer (δt\delta_{\text{t}}δt​) tends to be thinner compared to the hydrodynamic boundary layer (δh\delta_{\text{h}}δh​).
3. Ratio of Boundary Layer Thickness:
   • The ratio δhδt\frac{\delta_{\text{h}}}{\delta_{\text{t}}}δt​δh​​ for liquid metals is generally greater than 1. This indicates that the hydrodynamic boundary layer thickness is larger than the thermal boundary layer thickness.

Conclusion:

ANS:C - Bihar

Folk singer Maithili Thakur was appointed the state icon for Bihar by the Election Commission. The singer will create awareness among the voters for their participation in the electoral process.

ANS:A - February 4

The International Day of Human Fraternity is observed on February 4.

ANS:A - Manipur

Imoinu Iratpa festival is celebrated across Manipur.