Answer:
The magnitude of the frictional force is 
Explanation:
From the question we are told that
The force exerted on the box is 
Generally for the box to remain at rest then it means that the frictional force is greater than or equal to the force applied to move it i.e
=>
While the boy is sitting on the chair it creates a force downward on the chair and therefore the chair takes it and gives off the equal amount of force. So while he is putting force downward the chair is putting the same force upward.
Answer:
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Answer:
The materials with which the lab group are to use for the model includes;
i) A candle
ii) A match
iii) A strip of cloth
iv) Tongs
v) A metal can
The processes the lab group are to model are;
a) Conduction
b) Convection
c) Radiation
The procedure the lab group can use to do this is outlined as follows;
1) Tie the piece of cloth around the metal can with a strip of the cloth extending past the bottom of the can
2) Hold the metal can in with the aid of the tongs
3) Light the candle with the match
4) Place the metal can over over the burning candle so that it does not touch the flame
5) While holding the can with the tongs, ensure that the strip of cloth hanging by the side of the can does not come in contact with the flame
Conduction
Conduction heat transfer is observed by the rising temperature of the tongs that is in the contact with the can
Convection
Convection heat transfer is observed by the rising temperature of the can that is placed in the path of the rising convection current from the candle wax
Radiation
Radiation heat transfer is observed by the shrinking of the piece of cloth placed beside the candle flame
Explanation:
