As you walk to class with a constant speed of 1.60 m/s, you are moving in a direction that is 15.0° north of east. how long does it take you to move (a) 20.0 m east or (b) 30.0 m north?

Explanation:

Let east be positive x axis and north be positive y axis

Speed = 1.60 m/s in a direction that is 15.0° north of east.

Speed, v = 1.60 cos 15 i + 1.60 sin 15 j = 1.55  i + 0.414 j m/s

a) We need to find time taken to travel 20 m along east

Speed along east = 1.55 m/s

Distance = Speed x Time

20 = 1.55 x Time

Time = 12.90 seconds

Time taken is 12.90 seconds

b) We need to find time taken to travel 30 m along north

Speed along north = 0.414 m/s

Distance = Speed x Time

30 = 0.414 x Time

Time = 72.46 seconds

Time taken is 72.46 seconds