The answer is
This particular problem is about relative velocity. The given quantities are:
(velocity of the woman relative to the ground)
(velocity of the boy relative to the ground)
What we need to get is the velocity of the boy relative to the woman (). We can get that by using the formula
substituting all the given quantities that we have we get:
Therefore, the velocity of the boy relative to the woman is 10 m/s in the opposite direction.
I hope this helps.
The electromagnet could have good uses in industry because of its characteristics as a temporary magnet which looses its magnetic field when disconnect to the electric source. Such uses may include the cranes used in dragging metal scrap from a place to another.
While permanent magnegts can be seen inside different industrial machines that function through electromagnetic conduction.
The answer is 12 hours