Physics
posted by TechnoBoi11 .
An electron's position is given by r = 4.00t i  6.00t2 j + 5.00 k, with t in seconds and r in meters.
(a) In unitvector notation, what is the electron's velocity v(t)? (Answer in terms of i, j, k, and t.)
___ m/s
(b) What is v in unitvector notation at t = 8.00 s?
___ m/s
(c) What is the magnitude of v at t = 8.00 s?
___ m/s
(d) What angle does v make with the positive direction of the x axis at t = 8.00 s?
___ ° (from the +x axis)
..for (a), i got:
((d(4.00))/dt)i((d(6.00))/dt^2)j+((d(5.00))/dt)k
and for (b):
((d(4.00))/(d(8.00)))i((d(6.00))/(d(8.00^2)))j+((d(5.00))/(d(8.00)))k
what am i doing wrong?
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