What Are the Velocity and Acceleration of a Particle at t = 5.0 s?

[P-Illiterate]

A particle starts from the origin at t = 0 and moves along the positive x axis. A graph of the velocity of the particle as a function of the time is shown in Fig. 2-43;

the v-axis scale is set by vs = 7.00 m/s. (a) What is the coordinate of the particle at t = 5.0 s? (b) What is the velocity of the particle at t = 5.0 s? (c) What is the acceleration of the particle at t = 5.0 s? (d) What is the average velocity of the particle between t = 1.0 s and t = 5.0 s? (e) What is the average acceleration of the particle between t = 1.0 s and t = 5.0 s?

Homework Equations

V_f= V_i+at
V_avg = (V_f+V_i)/2
a _avg= change in v/change in time

The Attempt at a Solution

I think all my answers are wrong!
a) (2,5) --> Looking at the graph

b) t =5s, v=2 m/s

c) V_f= V_i+at
(4-2)/1 = a
a = 2 m/s

d) V_avg = (V_f+V_i)/2
(2=2)/2
= 2 m/s

e) a _avg= change in v/change in time
=0 m/s

 

[Thaakisfox]

you cannot calculate the coordinate by just looking at the graph. You have to use x=at^2/2
for b.) its just v_s/2 from the graph

c, how much the velocity decrease from t=4 to t=5? i.e. in one second?

d.) the formula is right but u read it wrong from the graph.

e,) correct.

 

[P-Illiterate]

for A, x=at^2/2
how do I find a??

Thanks though :D