xD_aQt's Physics Thread

[xD_aQt]

I have got no clue where to begin ... (Out of all my subjects, Physics I struggle the most!)

A force of 120 N is used to push a 20 kg shopping trolley along the line of its handle, which makes an angle of 20 degrees to the horizontal. This is enough to cause the trolley to travel with constant velocity to the north along a horizontal path.

a) Determine the horizontal and perpendicular components of the force applied to the trolley.

[Aden]

Imagine and draw a diagram of the trolley with the 120N Force acting on it at 20 degrees, then use trigonometry.

[superflya]

horizontal component= 120 x cos(20)
vertical component= 120 x sin(20)

[xD_aQt]

For the horizontal component, is it always cos ?
For the vertical component, is it always sin ?
Is there a general formual for these component, or would we just use trigonometry ?

[Aden]

If you're given the resultant force (hypotenuse) and angle, then yes. However, if you were given either the horizontal or vertical force and the angle, then you would need to use trigonometry (tan function in this case) to find the others. It is best to understand what these questions are asking, then take a few seconds to imagine what it looks like, and finally use trignometry to solve it.

[superflya]

yea it doesnt help to make such assumptions, always best to make a rough picture of all the info your given and work from there