Average Acceleration and Velocity Question

[CathyCat]

Homework Statement

An object traveling at a constant velocity v0 experiences a constant acceleration in the same direction for a period of time t. Then, an acceleration of equal magnitude is experienced in the opposite direction of v0 for the same period of time t. What is the object's final velocity? State the magnitude and direction.

Homework Equations

Acceleration=Vf-Vi/t

The Attempt at a Solution

i don't know what they are asking for, as in i don't understand the question
Thank you

 

[CathyCat]

can someone help me please. its a choice question as in the magnitude is a)more than initial magnitude, b)less than initial magnitude, and c)the same as the initial magnitude
and for the direction its a) same as initial magnitude or b) opposite of initial magnitude

 

[PeterO]

Homework Statement

An object traveling at a constant velocity v0 experiences a constant acceleration in the same direction for a period of time t. Then, an acceleration of equal magnitude is experienced in the opposite direction of v0 for the same period of time t. What is the object's final velocity? State the magnitude and direction.

Homework Equations

Acceleration=Vf-Vi/t

The Attempt at a Solution

i don't know what they are asking for, as in i don't understand the question
Thank you

To paraphrase the question:
You are traveling in a car on a straight road, heading East at 40 kph.
You press the accelerator so the car now accelerates at a rate of 5 kph/s East. You continue pressing the accelerator for 5 seconds [and will thus reach a new, higher speed.
You then carefully apply the brakes, so as to achieve an acceleration of 5 kph/s West [naturally the braking force/acceleration is in the direction opposed to the way you are travelling]. You maintain that braking rate for exactly 5 seconds.
What will your final velocity be? ie how fast will you be travelling, and are you going East or West?

If you are uncomfortable with kph [kilometres per hour] then change it to mph [miles per hour] but retain the figures - it just means a more significant speed at all times, but still not unreasonable.

Note:
While traveling East, an easterly acceleration means increasing speed [what usually happens when you press the accelerator].
While traveling East, a westerly acceleration means reducing speed or slowing down [what usually happens when you apply the brakes].