Forces on an inclined phase

Question 1

Resultant vector def

Answer 1

The single equivalent vector which can exactly replace a collection of vectors.

This can be found either by scale drawing or in the case of vectors at right angles Pythagoras’ theorem and trigonometry.

Question 2

Resolving Vectors Into Perpendicular Components

Answer 2

When confronted with a collection of vectors it is convenient to resolve each vector into equivalent perpendicular components.

Once all the components have been found the sum in each direction can be simply found. From this we can find the resultant vector.

Question 3

How can we find the Force down the slope and into a slope on an inclined phase?

Answer 3

It can be shown that for an object on a slope that:
Fdown slope = WsinΘ and Finto slope = WcosΘ

Question 4

Example q
The block is placed on a different slope with a frictional force of 1.35N. What is the resultant force acting down the slope?
What is the acceleration of the block?

Answer 4

Fres = Wsinθ − Ffriction = 5.4sin30 − 1.35 = 1.35N

m = W/g = 5.4/9.81 = 0.55kg

a = F/m = 1.35/0.55 = 2.45 ms−2