Answer:
Microwave: Radiation
Water: Conduction, convection & radiation.
Explanation:
- When we heat a food using microwave then the water content of the food is only heated by the microwave.
- Microwaves make the molecules of water vibrate frequently with a frequency closer to the frequency of microwaves and this increases the kinetic energy of the molecules which produces heat in the water molecules this heat then propagates to the whole food by conduction and convection, but the heat enters the food only via radiation.
Now when the food item is kept into warm water then the molecules closer to the food heat the food by conduction through direct energy transfer by lattice vibrations and when they become cooler than the mass of water all around then due to density difference they settle down and their place is occupied by warmer molecules around in the fluid leading to convection.
Radiation of energy from a mass occurs continuously irrespective of the medium present there. So the heat of water also enters the food by radiation of energy from the water molecules.
Answer: False
Sorry if this is wrong I’m not positive this answer is right but you can still try it. :)
Answer:
<em>Load</em>
Explanation:
<em>The load in an electric circuit is any device that converts electrical energy into another form of energy.</em>
The correct matches are as follows:
<span>1. Mechanical Energy
</span>This is the energy of motion and position - Kinetic Energy and Potential Energy are included here.
<span>
2. Electrical Energy
</span>This is the type of energy that is given off as a result of electrons (charges!) moving through a conductor.
<span>
3. Light Energy
</span>This is the only form of energy we can see with our eyes!
<span>
4. Thermal Energy
</span>This is heat energy! It can be transferred through conduction, convection, or radiation.
<span>
5. Sound Energy
</span>This is energy that is transmitted through vibrations.
<span>
6. Kinetic Energy
</span>This is the energy that all moving objects have. <span>
7. Potential Energy
</span>This is stored energy, waiting to be used!
Answer:
Vs = 6.73 m/s or Vs = 16.3 m/s
Explanation:
frequency of the trains whistle (f) = 1.64 x 10^{2} Hz = 164 Hz
frequency of beats heard = 4 beats/s = 4 Hz
velocity of the stationary train (Vr) = 0
velocity of sound in air (V) = 343 m/s
velocity of the moving train (Vs) = ?
we can get the velocity of the moving train from the formula below
Fn = f x 
...equation 1
where Fn = net frequency
- case one - assuming the train is approaching the station Fn = 164 + 4 = 168 Hz
substituting the known values into equation 1
168 = 164 x 
1.02 =
Vs = 
Vs = 6.73 m/s
- case two - assuming the train is leaving the station Fn = 164 - 4 = 160 Hz
substituting the known values into equation 1
168 = 160 x
1.05 =
Vs = 
Vs = 16.3 m/s
