Displacement Vector of Minute Hand: 8-8:20 & 8-9:00 a.m.

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To calculate the displacement vector of the minute hand from 8:00 to 8:20 a.m., the formula \vec r(t) = \hat i L \sin \left( 2 \pi \frac {T}{12} \right) + \hat j L \cos \left( 2 \pi \frac {T}{12} \right) can be applied, with L being 2.0 cm and T set to 1/3 for 20 minutes. For the time interval from 8:00 to 9:00 a.m., T would be 1, representing one full hour. The discussion highlights the need for understanding how to apply the formula to find the x and y components of the displacement vector. Visual aids may be necessary for better comprehension of the minute hand's movement.
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The minute hand on a watch is 2.0 cm in length. What is the displacement vector of the tip of the minute hand

From 8:00 to 8:20 a.m.? Express vector r in the form r_x, r_y, where the x and y components are separated by a comma.

and

From 8:00 to 9:00 a.m.? Express vector r in the form r_x, r_y, where the x and y components are separated by a comma.

I am no idea how to do these problems. could someone give some suggestions as to how to begin?
 
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\vec r(t) = \hat i L \sin \left( 2 \pi \frac {T}{12} \right) + \hat j L \cos \left( 2 \pi \frac {T}{12} \right)

where L is the length of the minute hand and T is the time measured in hours.
 
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