**Next:** About this document

MATH 1300.03F D **Quiz 9** Friday, November, 19 1999

NAME:

Student Number: No.Marks

(2 Marks) The position *s*(*t*), at time *t*, of an object is given by

(1) Find the velocity of the object at time *t*.

(2) Find the acceleration of the object at time *t*.

(3) Use a number line to sketch the motion of the object, indicate the direction of motion, and indicate where the object is slowing down and where it is speeding up.

Solution. (1) The velocity of the object at time *t* is

Let *v*(*t*)=0. Noting that *v*(*t*)=3(*t*-6)(*t*+2), we
have *t*=6 and *t*=-2.

(2) The acceleration of the object at time *t* is

Let . Then *t*=2.

(3) We list the following table.

Fri Nov 19 15:04:00 EST 1999