Answer:

Explanation:
We should first find the velocity and acceleration functions. The velocity function is the derivative of the position function with respect to time, and the acceleration function is the derivative of the velocity function with respect to time.

Similarly,

Now, the angle between velocity and acceleration vectors can be found.
The angle between any two vectors can be found by scalar product of them:

So,

At time t = 0, this equation becomes

1. Is A. at the poles because thats where the magnetic field is going out then coming back into the earth to produce the magnetic field.
2. Again its A. because the compass needle is attracted to " north " which is magnetic south. It does this because opposites attract.
3. This one would be B. Because if the magnets were being repelled the magnetic field lines would look like there was a line that the field hit and bounced off of it.
4. This answer is A. the magnetite helps them migrate so they know which way is north and which way is south.
5. This answer is A. Because without the domains there wouldn't be poles on the magnetic object. <span />
Answer:
The average speed can be calculated as the quotient between the distance travelled and the time needed to travel that distance.
To go to the school, he travels 2.4 km in 0.6 hours, then here the average speed is:
s = (2.4km)/(0.6 hours) = 4 km/h
To return to his home, he travels 2.4km again, this time in only 0.4 hours, then here the average speed is:
s' = (2.4 km)/(0.4 hours) = 6 km/h.
Now, if we want the total average speed (of going and returning) we have that the total distance traveled is two times the distance between his home and school, and the total time is 0.6 hours plus 0.4 hours, then the average speed is:
S = (2*2.4 km)/(0.6 hours + 0.4 hours)
S = (4.8km)/(1 h) = 4.8 km/h