The answer is B! Hope this helps
I can't eliminate answers. Some of them are just wrong. A is incorrect. There is no such thing as a 1 pole magnet.
I wouldn't use B. If it is just a bar it is not a magnet.
C is the traditional answer
D is a space filler. It is just there to occupy a letter.
Force is calculated F=m×a.
If both ships speed up with the same force, but have a different mass, This means that a also has to be different. If F is the same but ship a has a bigger mass(m) than ship b, then the acceleration(a) of ship b has to be bigger so F of each ship is the same. So the ship with the smaller mass will speed up faster.
Answer:
1.89mol
Explanation:
The entropy change during free expansion is express as
Where S is the entropy of the system,
n is the amount of mole
R is the gas constant = 8.314 and
V is the volume occupied at the initial and final stage
since the process is n adiabatic free expansion, the entropy of the system is constant. Hence we can re-write the equation as
where the 
and 
and
Now if we substitute in values we arrive at
Answer:
21/5 seconds or 4.2 seconds
Explanation:
Distance=Speed*Time
21=5 *Time
21/5=Time
4.2=time
