Q.11)-Burns caused by steam cause much more irritation than those caused by boiling water because
- Temperature of steam is higher
- Steam has latent heat of vaporization
- Steam is a gas and engulfs the pores of body quickly
- Steam pierces through the pores of body quickly
Q.12)-Convection occurs in which of the following
- Only solids and liquids
- Only liquids and gases
- Only gases and solids
- Solid, liquid and gases
Q.13)-Which of the following liquid contains highest rate of vaporization
- Kerosene oil
- Water
- Petrol
- Alcohol
Q.14)-The hottest part of gas flame is known as
- Non-luminous zone
- Blue zone
- Luminous zone
- Dark zone
Q.15)-Earth is a
- Good reflector of heat
- Bad absorber of heat
- Good absorber and good radiator of heat
- Bad absorber and bad radiator of heat
Q.16)-Why are the handles of metallic teapots made of wood?
- Wood is a bad conductor of heat
- It does not cause electric shocks
- It makes contqainers look beautiful
- It makes containers look clean
Q.17)-Why two thin shirts can keep us warmer than a single thick shirt in winters?
- Two shirt become thicker so present the permission of heat
- Layer of shirt acts as a conductor of heat between two shirts
- Layer of air acts as an insulating medium between two shirt
- Radiation of heat doesn't take place
Q.18)-Energy travels from sun to earth by which of the following method
- Conduction
- Insolation
- Radiation
- Modulation
Q.19)-The characteristics invalid for heat radiation is that it travels
- In a straight line
- In all direction
- With the speed of light
- Heating the medium through which it passes
Q.20)-Which of the following is a good conductor of heat but bad conduction of electricity
- Mica
- Asbestos
- Celluloid
- Paraffin wax