Q1. Wet clothes are hanged on a clothesline outdoors in sub-zero weather. After a day, the clothes are brought into the house....... Question 2. Your finger sticks to an ice tray just taken from the refrigerator......... .?

Q1. Wet clothes are hanged on a clothesline outdoors in sub-zero weather. After a day, the clothes are brought into the house and observed to be dry. The process of drying is best explained as

(A) vaporization

(B) sublimation

(D) condensation

Ans: (B) sublimation

*sub-zero weather= temperature of environment below 0° Centigrade in india and in United States below 0° Fahrenheit

*Sublimation : phase transition of substance from solid to gas state, without passing through the liquid state

Solid ------sublimation------------> Gas

Solid <----------------Desublimation---Gas

Solid --------- melting---------------->liquid

Solid <----------- freezing------------liquid

Liquid ------------- vaporization------> Gas

Liquid<--------------- condensation----- Gas

Question 2. Your finger sticks to an ice tray just taken from the refrigerator. Which factor has more effect on this phenomenon?

(A) the inside temperature of the freezer

(B) the humidity of the air

(D) the thermal conductivity of the tray

Ans: (D) the thermal conductivity of the tray

*Thermal conductivity: thermal conductivity is the property material used for how fast heat can transfer from one point to another point of metal and non-metal, that is denoted by "K" and unit is watt/meter kelvin

K=Qd/AΔT

K= thermal conductivity

Q=amount of the transferred

d= distance between the two isothermal planes

ΔT= difference in temperature

Comments

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