I have the exact same question, any chance you figured it out since you posted this?
<em>A</em> - <em>B</em> = (10<em>i</em> - 2<em>j</em> - 4<em>k</em>) - (<em>i</em> + 7<em>j</em> - <em>k</em>)
<em>A</em> - <em>B</em> = 9<em>i</em> - 9<em>j</em> - 3<em>k</em>
|<em>A</em> - <em>B</em>| = √(9² + (-9)² + (-3)²) = √189 = 3√19
The factors which are affected will be based on the distance or range between the charged objects A and B
<u>Explanation:</u>
<u>Definition:</u>
- The force, F among the two-point size charges A and B are divided by a range r is given by Coulomb formula.
F=9x10^9 AB/r²
<u>Factors:</u>
- If the range among them is doubled the force will be decreased to 1/4 of the initial value. And if the range is split, the force will be four times.
- If the range among them is tripled, the force will be decreased to 1/9 of the initial value. If the range is decreased to one-third of the new value, the force will rise to Nine times the initial value.
Answer:
The correct option is that (She decreases her moment of inertia, thereby increasing her angular speed.)
Explanation:
When an object is in circular motion, the vector that describes it is known as angular momentum. Angular momentum is conserved or constant when an object is spinning in a closed system and no external torques are applied to it. An example of conservation of angular momentum is seen when a woman is sitting on a spinning piano stool with her arms extended. Her angular momentum is conserved because the net torque on her is negligibly small as the friction is exerted very close to the pivot point.
When she folds her arms,her rate of spin increases greatly decreasing her moment of inertia. The work she does to pull in her arms results in an increase in rotational kinetic energy( that is, increase in her angular speed). I hope this helps, thanks!
Answer:
The magnitude of magnetic field decreases in comparison to previous case.
Explanation:
Let current flowing in two conductors are
and 
Magnetic field in wire,
Magnetic field due to current I1

Magnetic field due to current I2

When two parallel conductors are carrying currents in the same direction then the magnetic field will be added.

When the direction of one of the current is reversed then the magnitude of the magnetic field midway between them


Hence, the magnitude of magnetic field decreases in comparison to previous case.