Explanation

• Urea is produced by reacting ammonia (NH₃) with carbon dioxide (CO₂) under high pressure and temperature.
• The urea solution is concentrated by removing excess water, producing molten urea.
• Molten urea is then converted into solid granules or prills for storage and transportation.

Last verified on 01-11-2026

Explanation

• Lewis relationship connects heat transfer and mass transfer in fluid systems.
• Lewis number is ratio of thermal diffusivity to mass diffusivity, Le = alpha / D_AB.
• It is important in evaporation, humidification and drying processes.
• For air-water system Le is about 1.

Last verified on 01-11-2026

Explanation

• Joule-Thomson coefficient measures how temperature changes when pressure changes at constant enthalpy.
• Its formula is mu_JT = (dT/dP)H.
• On inversion curve mu_JT is zero, so pressure change does not change temperature at that point.

Last verified on 01-11-2026

Explanation

• At 0K heat capacity of every substance becomes zero, so value is same for all.
• At absolute zero there is no heat energy left to store, entropy also becomes zero.
• At other temperatures like low or optimum temperature, heat capacity is different for different materials.

Last verified on 01-11-2026

Explanation

Explanation

• Destructive interference occurs when two waves meet and their displacements cancel each other.
• It occurs when the path difference is an odd multiple of half the wavelength.
• Complete cancellation occurs when the waves have equal amplitudes and are exactly opposite in phase.

Last verified on 31-10-2026

Explanation

Explanation

• In longitudinal waves, particles of the medium vibrate parallel to the direction of wave propagation.
• These waves consist of compressions and rarefactions.
• Sound waves in air are a common example of longitudinal waves.

Last verified on 31-10-2026

Explanation

Given:

Object distance (u) = 30 cm

Focal length (f) = 15 cm

2 x f = 2 x 15 = 30 cm

So object is at 2F.

Lens formula:

1/f = 1/v + 1/u

1/15 = 1/v + 1/30

1/v = 1/15 - 1/30

1/v = 1/30

v = 30 cm

Image also forms at 30 cm on other side.

Magnification = v / u = 30 / 30 = 1

Magnification 1 means image size = object size.

Answer: The same - inverted and same size.

Last verified on 31-10-2026

Explanation

• Blue light has the shortest wavelength.
• In the visible spectrum, wavelength decreases from red to violet.

Additional information:

• Red light rays have the lowest frequency and highest wavelength value.

Last verified on 10-06-2026