# Physics

Hot air rises and cold air sinks. So in which condition will a switch of a fan heater be open or close ?
Thanks (:

1. 👍 0
2. 👎 0
3. 👁 138
1. You want the fan on to move the hot air at the ceiling around the room.

1. 👍 0
2. 👎 0

## Similar Questions

1. ### Physics

Hot air balloons float in the air because of the difference in density between cold and hot air. In this problem, you will estimate the minimum temperature the gas inside the balloon needs to be, for it to take off. To do this,

asked by Jenny on July 13, 2011
2. ### Physics, Math

A typical volume of a modern hot air balloon is 2500 cubic metres, and a typical maximum temperature of the hot air is 120 degrees Celsius. Given these figures, and an outside air temperature and density of 15 ∘C and 1.225 kg/m3

asked by Luis on September 2, 2014
3. ### Physics

An automobile tire contains a certain volume of air at 30 psig and 70 °F. The barometric pressure is 29.50 Hg. If due to running conditions, the temperature of air in the tire rises to 160 °F. What will be the gauge pressure?

asked by Janus on February 22, 2010
4. ### Chemistry

The total mass that can be lifted by a balloon is given by the difference between the mass of air displaced by the balloon and the mass of the gas inside the balloon. Consider a hot air balloon that approximates a sphere 5.00 m in

asked by Savannah on December 16, 2012
1. ### Physics

A jetliner flies west 2,000 miles from Chicago you San Francisco. It has an average speed of 635 mph relative to the air. What is the velocity of the jetliner relative to the earth of the wind is blowing at 160 mph from the west

asked by Helga on August 27, 2018
2. ### Science

When you put your hand near a candle, you feel heat directly over the flame but cool on the sides of the flame. Why does this difference occur? I think because of convection the warmer air rises and the cooler air sinks.

asked by ❄ Snowflake ❄ on March 9, 2020
3. ### Physics

A sound wave is traveling in warm air when it hits a layer of cold, dense air. If the sound wave hits the cold air interface at an angle of 23 degree angle, what is the angle of refraction? Assume that the cold air temperature is

asked by melissa on December 13, 2012
4. ### physics

A typical volume of a modern hot air balloon is 2500 cubic metres, and a typical maximum temperature of the hot air is 120 degrees Celsius. Given these figures, and an outside air temperature and density of 15 \(^{\circ}C\) and

asked by Nick on March 27, 2014
1. ### Physics-Need Help fast!

Part 1 A 3m long pipe is in a room where the temperature is 20 degrees C. What is the frequency of the first harmonic if the pipe is closed at one end? Part 2 sound traveling in air at 23 degrees C enters a cold front where the

asked by Megan on July 27, 2011
2. ### science

when that air under the envelope is heated , the balloon lifts . which of the following statement is true A. hot air balloons use radiation to rise B. hot air balloons use conduction to rise C. hot air balloons use convection to