Question

The equation of motion:

r = -10i + 15t j + 5t2k

Q: (1)The average velocity from t=Is to t=2s

(2) The instantaneous velocity and acceleration at t=2s.

Answer 1

$v=15j+10tk,$

$a=10k,$

$v(2)=15j+20k,$

$a(2)=10k.$