What is the average acceleration of a jet ski that goes from rest to 10 m/s west in 4 s? Take the direction west to be positive, and east to be negative.

A.
2.5 m/s2

B.
-2.5 m/s2

C.
0.4 m/s2

D.
-0.4 m/s2

Question

What is the average acceleration of a jet ski that goes from rest to 10 m/s west in 4 s? Take the direction west to be positive, and east to be negative.	
 
 A.
2.5 m/s2
 
 B.
-2.5 m/s2
 
 C.
0.4 m/s2
 
 D.
-0.4 m/s2

danjs · Answer

THe average acceleration is the slope of a secant line connecting those 2 given points

danjs · Answer

(v(4) - v(0))  /  ( 4 - 0 )

anonymous · Answer

uh?

danjs · Answer

v(4) = 10 m/s
v(0) = 0 m/s   rest

danjs · Answer

$$<a> = \frac{ v(4) - v(0) }{ 4-0 } = \frac{ 10 - 0}{ 4 - 0 } ~m/s^2$$

anonymous · Answer

Uh sorry, i just dont understand, just too confused.
A = ?
V = ?
M/S = ? (Meters per second?)
Anyway im just really running out of time so if someone could just help me asap it would really save me!