Question

5.
A particle moving with a constant speed describes a circular path whose position
vector relative to the origin at center is given by r = 5(cos tỉ sin tj) m, where
a is in rad/s and t is in s. What is its centripetal acceleration at t = 2 s?
(1) 15a2 m/s2
(2) 5a² m/s²
(3) 10a2 m/s2
(4) 100 m/s2​

Answer 1

Answer:v=  

dt

dr

​  

=15p(−sinpt  

i

^

+cospt  

j

^

​  

)

r= 15 m ⇒a  

c

​  

=  

r

v  

2

 

​  

=  

15

15  

2

p  

2

 

​  

=15p  

2

v=  

dt

dr

​  

=15p(−sinpt  

i

^

+cospt  

j

^

​  

)

r= 15 m ⇒a  

c

​  

=  

r

v  

2

 

​  

=  

15

15  

2

p  

2

 

​  

=15p  

2

Explanation: