Answer:
The lines of the magnetic field from a bar magnet form closed lines. By convention, the field direction is taken to be outward from the North pole and into the South pole of the magnet. Permanent magnets can be made from ferromagnetic materials.
As can be visualized with the magnetic field lines, the magnetic field is strongest inside the magnetic material. The strongest external magnetic fields are near the poles. A magnetic north pole will attract the south pole of another magnet, and repel a north pole.
Answer: 1.95s
Explanation:
Given
ma = 290 cos 34.9 - fk
fk = 290 cos 34.9 - ma
fn = mg + 400 sin Φ
fn = 290 + 400 sin 34.9
fn = 290 + 228.9
fn = 518.9
fk = fn * uk
uk = 0.57
290 cos 34.9 - ma = 518.9 * 0.57
290 cos 34.9 - ma = 295.8
290 cos 34.9 - 295.8 = ma
ma = -58
m = 290/10 = 29
a = 58/29
a = 2
Using equation of motion
S = ut + .5at²
3.8 = 0 + .5*2*t²
3.8 = t²
t = 1.95s
A constant velocity implies the two forces must be equal and opposite.
Friction acts horizontal to the ground, therefore we must find the force applied to the sled rope that acts horizontal to the ground.
Do this by resolving:
Force = 80cos53
The force opposing this is equal, and so also = 80cos53 = 48 N (2 sig. fig.)
Work done = Force X Distance
3 430 000J = Force X 14m
Force = 3 430 000J / 14m
= 245 000 N
Hope this helps!
Explanation:
Tremendous heat and pressure within the earth cause the hot magma to flow in convection currents. These currents cause the movement of the tectonic plates that make up the earth's crust.
