Answer:
Zero; no force is required to keep it going
Explanation:
Since the cannon ball is fired into frictionless space, there will be nothing to stop it, so it will keep going and going.
Answer:
This all simply due to the size of the two water bodies question and the your body size in a bath tub the water is small enough to allow the upthrust displace water out if the tub whereas in a lake the water is bigger and your body size is smaller to allow any noticeable upthrust that would cause an overflow
The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be quickly changed by controlling the amount of electric current in the winding. However, unlike a permanent magnet that needs no power, an electromagnet requires a continuous supply of current to maintain the magnetic field.
(-5)/3 - 6/(-5)
You can solve it now :)