Answer:
An object which moves in the positive direction has a positive velocity. If the object is slowing down then its acceleration vector is directed in the opposite direction as its motion (in this case, a negative acceleration).
Explanation:
Answer:
The voltage across a semiconductor bar is 0.068 V.
Explanation:
Given that,
Current = 0.17 A
Electron concentration 
Electron mobility 
Length = 0.1 mm
Area = 500 μm²
We need to calculate the resistivity
Using formula of resistivity


Put the value into the formula


We need to calculate the resistance
Using formula of resistance



We need to calculate the voltage
Using formula of voltage

Put the value into the formula


Hence, The voltage across a semiconductor bar is 0.068 V.
Average speed=total distance travelled/time
Answer:
A and E.
Explanation:
Physical properties have to do with things that are not done chemically.
A has to do with light that you can see.
B has to do with Ph (If not A this is your next answer)
C mentions a Patina which is a chemical reaction known as oxidation
D has to do with chemical reactions
E is always correct. One of the fundamental laws about matter is that it must always have mass.
I am 99% confident in A and E as your answer, but if it is wrong go with B and E.
Hope this helps!