A magnet is made from materials that is magnetized and create its own persistent magnetic field while a electromagnet is mad from coil of wire which acts as a magnet when electric current passes through it.
Answer:
The answer is C (The cost of the solar panels can be very high.)
Let's take the positive x-direction towards east and the positive y-direction towards south. The momentum must be conserved on both directions, after the collision. On the x-direction, initially we have only momentum from car 1, while on the y-direction initially only car 2 contributes to the total momentum of the system. After the collision, the two cars will move together with a total mass (m1+m2) and with final velocity vf, which can be decomposed on both directions. All of this translates into the equations:
(1)
(2)
where
,
,
and
.
and
are the components of the final velocity on both axes x and y.
By dividing equation (2) by (1), we get:
And the tangent of this ratio gives exactly the angle of the velocity vf in the south-east direction, with respect to the positive x-axis, so it gives us the direction of the final velocity:
+1
An electron has a negative charge so losing a charge of -1 from an uncharged, or neutral, atom will leave an ion with a positive charge.