Answer:
During convection, hot material expands & rises then moves to the side and cools & sinks. this circular pattern is called a convection current.
Explanation:
Convection is one of the three methods of transfer of heat. It occurs only in fluids (liquids or gases).
Convection occurs when there is a source of heat that heats a fluid, such as in a boiling pot of water. The water which is on the bottom of the pot becomes warmer before than the water at the top (because it is closer to the flame), and so it becomes less dense: for this reason, it expands and it becomes rising. On the contrary, the water on top is colder, so it is more dense and starts sinking, replacing the warmer water. As the new part of water gets warmer, it starts rising, and so the process is continuously repeated. This circular current is called convection current.
Answer:
11300 kgm3
Hope this helps
Answer: 14 m/s
Explanation:
The speed 
of a sound wave is given by the following equation:
Where:
is the wavelength of the sound wave
Hence:
Answer:
90 ohms
Explanation:
1/r = 1/180 + 1/180
1/r= 2/180
take the reciprocal of 2/180 which is 180/2 and its 90 ohms
It becomes a positive Iron
