Super Quick M1 Bearings Question

My attempt (or have I gone wrong somewhere in the drawing)

Question:

In an orienteering exercise, a team hike 8 km from the starting point,S, on a bearing of 300 then 6 km on a bearing 040 to the finishing point,F. Find the magnitude and direction of the displacement from S to F.

Reply 1

lizard54142

6

Original post by creativebuzz

My attempt (or have I gone wrong somewhere in the drawing)

Question:

In an orienteering exercise, a team hike 8 km from the starting point,S, on a bearing of 300 then 6 km on a bearing 040 to the finishing point,F. Find the magnitude and direction of the displacement from S to F.

I believe your diagram is incorrect.

Reply 2

creativebuzz

OP

2

Original post by lizard54142

I believe your diagram is incorrect.

Where have I gone wrong?

Reply 3

lizard54142

6

Original post by creativebuzz

Where have I gone wrong?

The "40 degrees" should be on the other side of the line. It might help if you draw north as straight up.

Reply 4

creativebuzz

OP

2

Original post by lizard54142

The "40 degrees" should be on the other side of the line. It might help if you draw north as straight up.

But

The mark scheme says this:

Attachment not found

So my 40 is correct but not my 60 and I don't know why :/

Original post by creativebuzz

But

The mark scheme says this:

Attachment not found

So my 40 is correct but not my 60 and I don't know why :/

It's because you're assuming that the second route will finish at the north-line, it doesn't! Your angles are all correct but the length of the second route is incorrect.

Reply 6

creativebuzz

OP

2

Original post by lizard54142

It's because you're assuming that the second route will finish at the north-line, it doesn't! Your angles are all correct but the length of the second route is incorrect.

Ah I understand what you're saying! But in the mark scheme, why did they put the 60 degrees there/where did that come from/what rule?

Reply 7

lizard54142

6

Original post by creativebuzz

Ah I understand what you're saying! But in the mark scheme, why did they put the 60 degrees there/where did that come from/what rule?

Notice the vertical dashed line at S... the angle between this line and the first route is 60 degrees, so they've just used the "F" angle rule (can't remember the proper name from GCSE, corresponding angles I think).

Reply 8

creativebuzz

OP

2

Original post by lizard54142

Notice the vertical dashed line at S... the angle between this line and the first route is 60 degrees, so they've just used the "F" angle rule (can't remember the proper name from GCSE, corresponding angles I think).