8. In soft magnetic materials such as iron, what happens when an external magnetic field is removed?
a. The domain alignment persists.
b. The orientation of domains fluctuates.
c. The material becomes a hard magnetic material.
d. The orientation of domains changes, and the material returns to an unmagnetized state.
9. According to Lenz’s law, if the applied magnetic field changes,
a. the induced field attempts to keep the total field strength constant.
b. the induced field attempts to increase the total field strength.
c. the induced field attempts to decrease the total field strength.
d. the induced field attempts to oscillate about an equilibrium value.
10. The direction of the force on a current-carrying wire in an external magnetic field is
a. perpendicular to the current only.
b. perpendicular to the magnetic field only.
c. perpendicular to the current and to the magnetic field.
d. parallel to the current and to the magnetic field
I think the answer is potential
The fraction of radioisotope left after 1 day is 
, with the half-life expressed in days
Explanation:
The question is incomplete: however, we can still answer as follows.
The mass of a radioactive sample after a time t is given by the equation:
where:
is the mass of the radioactive sample at t = 0
is the half-life of the sample
This means that the mass of the sample halves after one half-life.
We can rewrite the equation as
And the term on the left represents the fraction of the radioisotope left after a certain time t.
Therefore, after t = 1 days, the fraction of radioisotope left in the body is
where the half-life must be expressed in days in order to match the units.
Learn more about radioactive decay:
brainly.com/question/4207569
brainly.com/question/1695370
#LearnwithBrainly
Explanation:
It is given that,
A car travels 25 m/s forward for 10 s.
Solution,
For a vector, a quantity must have both magnitude as well as the direction. For a scalar, a quantity have only the magnitude. In this case, the car moves in forward direction. This is the only difference between the vector and the scalar.
Out of given option,s the correct option is (c) "The measurement 25 m/s is the only vector quantity because it is a measurement of speed".
That's "displacement". It only depends on the beginning and ending locations, and doesn't care about the route between them.
