Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

(1 point) A particle moves along a straight line and its position at time t is g

ID: 2886111 • Letter: #

Question

(1 point) A particle moves along a straight line and its position at time t is given by s(t)-t*-10t +18, t20, where s is measured in feet and t in seconds. (A) Find the velocity at time t v(t) (B) Find the velocity (in tu/sec) of the particle at time t 3. (C) Find all values of t for which the particle is at rest. (If there are no such values, enter none. If there are more than one value, list them separated by commas.) t- (D) Use interval notation to indicate when the particle is moving in the positive direction. (If needed, enter inf for oo. If the particle is never moving in the positive direction, enter none .) (E) Find the total distance traveled during the first 8 seconds

Explanation / Answer

a)

v(t) =ds/dt

=4t^3 -10

b)

V(3) = 4*3^3 -10

=98 ft/sec

c)

V(t) =0

4t^3 -10 =0

t^3 =10/4

t=(5/2)^(1/3) which is about 1.3572 seconds

d)

Interval is ((5/2)^(1/3) , ) or say (1.3572, )

e)

Total distance is

S= |S(1.3572) -S(0)| +|S(8) -S(1.3572))

=|(7.8209-18)| +|(4034-7.8209)|

=4036.36