Answer:
Multiple choice answer would be "None"
Explanation:
White dwarfs are radiating stored heat from earlier reactions.
Technically, it would be the last fusion stage the star went through
BEFORE it became a white dwarf, but that's nit-picking.
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:
Answer:
71.8 N
Explanation:
T = Tension force in the strap
W = net work done = 752 J
f = force of friction = 8 N
d = displacement = 15 m
θ = angle between tension force and horizontal displacement = 36 deg
work done by frictional force is given as
W' = - f d
Work done by the tension force is given as
W'' = T d Cos36
Net work done is given as
W = W' + W''
W = T d Cos36 - f d
752 = T (15) Cos36 - (8) (15)
T = 71.8 N
Answer:
reactants
Explanation:
The reaction model is given as shown below:
4Fe + 3O₂ → 2Fe₂O₃
The name that describes the iron and oxygen found on the left hand side of Leann's model is reactants.
Reactants in a chemical expression are the species that are combining together to give a product.
Some reactions only have one reactant and such a chemical process is often termed decomposition reaction.
The two moles of Fe₂O₃ is the product of the reaction.
Required Heat = Q
Q = Mass * specific heat of water * change in temp.
Q = 5g * 1g/cal*degC * 20degC
Q = 100 cal of heat is required
To convert calories to Joules,
1 cal = 4.184 Joules
100cal = 418.4 J of heat is needed
