a particle moves around the circle along a path r(t) = cos(t)i + sin(t)j

a) find particle velocity
b) does particle have constant speed
c) show particle velocity vector is always orthogonal to position vector

Question

a particle moves around the circle along a path r(t) = cos(t)i + sin(t)j 

a) find particle velocity 
b) does particle have constant speed
c) show particle velocity vector is always orthogonal to position vector

anonymous · Answer

velocity is the first derivative but constant speed?

anonymous · Answer

Aizam wish to visit the red giant star Betelgeuse, which is 430 light-years away,
and that he want his 20,000 kg spaceship to move so fast that he ages only 20
years during the round trip. How fast must his spaceship travel relative to the
earth

anonymous · Answer

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