Super! Weight always acts downwards towards the Earth. So, weight must have the downward arrow. The tension on an object is in a direction along the rope, and away from the object. So, the tension must be in the upward direction.

Until now, our co-ordinate system has been:

The +y directions is

**horizontal and to the right**is +x, whereas**vertical and upwards**is +y. For inclined plane problems, it is useful to choose a different co-ordinate system.The +y directions is

**perpendicular to the plane and upwards**. The +x direction is**parallel to the plane, upwards along it**.In this new system, which forces are

**exactly**along the x and which are**exactly**along the y direction?- Normal Force is along +y and Frictional Force is along -x
- Normal Force is along +y and Frictional Force is along +x
- Normal Force and Weight are along +y and Frictional Force is along +x
- Weight is along +y and Frictional Force is along +x