Calculating distance II

Calculating distance II

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This task is about using trigonometry to calculate distances in practical problems.
trig-ratios.png Use the formulae in the box to answer the following questions.

Question 2Change answer

a)
A jet plane climbs at an angle of 60° and travels a distance of 3000 metres.
diagram of jet plane climbing  [Not drawn to scale]
     How far has the plane travelled in the horizontal direction, shown by 'w'? metres

Question 2Change answer

b)
A submarine dives at an angle of 40° for 935 metres.
diagram of submarine diving  [Not drawn to scale]
     Calculate the depth the submarine will be at after the dive, shown by 'x'.  metres

Question 2Change answer

c)
Simon and Maraea are playing golf. Maraea is 110 metres away from the hole.
Simon is standing at an angle of 17° from Maraea and the hole.
 
  diagram of two friends and a hole on a golf course  [Not drawn to scale]
     How far is John from the hole, shown by 'y'?  metres

Question 2Change answer

d)
Josh watched a space shuttle launch. When the space shuttle was 15 km above the Earth, there was an angle of 60° between where Josh was standing, the space shuttle, and the launch site.
 diagram of space shuttle after launch   [Not drawn to scale]
     Calculate how far Josh was from the launch site, shown by 'z'.  km
Task administration: 
This task can be completed with pen and paper or online (with NO auto marking).
Level:
5
Description of task: 
Using given trigonometry ratios, students calculate distances in practical problems.
Answers/responses: 
 

Y10 (10/1998)

a) 1500 moderate
b) 601          [Accept 600-601.5] moderate
c) 115.03     [Accept 115-115.1] very difficult
e) 8.66         [Accept 8.6-8.7] difficult
Diagnostic and formative information: 
  Common error Likely calculation Likely reason
c) 105 or close 110 cos 17° Wrong manipulation of 110 ÷ y = cos 17°.
d) 25.9, 26, 25 or close13 15 tan 60°15 tan 60° ÷ 2 Wrong manipulation of 15 ÷ z = tan 60°.As above but halves answer to make it look plausible.