Answer:
a
The time it would take the beef to reach a temperature of 0⁰C is t= 662 sec = 11.93 min
b)
The time it would take to heat the beef to uniform temperature of 80⁰C is
t = 365 sec =5.93 min
c
Efficient absorption of Microwave power is in regions of liquid water . Hence if the food or the microwave irradiation is not uniform, the power will be absorbed non-uniformly, resulting in a non-uniform temperature rise. Defrost region will absorb more energy per unit volume than frozen region.if food is of low thermal conductivity, there will be insufficient time for heat conduction to make the temperature more uniform.Use of low power allows more time for conduction to occur.
Explanation:
The explanation is shown on the first second and third uploaded image
Answer:
2.9Ω
Explanation:
Resistors are said to be in parallel when they are arranged side by side such that their corresponding ends are joined together at two common junctions. The combined resistance in such arrangement of resistors is given by;
1/Req= 1/R1 + 1/R2 + 1/R3 .........+ 1/Rn
Where;
Req refers to the equivalent resistance and R1, R2, R3 .......Rn refers to resistance of individual resistors connected in parallel.
Note that;
R1= 6.0Ω
R2 = 9.0Ω
R3= 15.0 Ω
Therefore;
1/Req = 1/6 + 1/9 + 1/15
1/Req= 0.167 + 0.11 + 0.067
1/Req= 0.344
Req= (0.344)^-1
Req= 2.9Ω
The answer would be:
The comb gains electrons.
The hair loses electrons.
In chemistry, the charge depends on the electrons and protons. The electron will give negative charge and proton will give the positive charge. Proton is located in the nucleus of the atoms so it won't easily move like electron which located in the orbit in the atoms perimeter. So, ignore the option with the proton.
If the combs become negatively charged, that means it gain some electron. Since something gain electron, that means another thing is losing an electron. That electron comes from the hair.
To solve this problem we will resort to the concept of angle of incidence and refraction.
Since it is a reflection on a mirror, the angle provided for refraction will be equal to that of the incidence, that is, 25 °
The angle of reflation is always perpendicular to the surface so it is necessary to find the angle with respect to it.
Therefore the angle of the reflected beam of light made with the surface normal is 65°
Northern Australia. hope that helps