A car is moving with a constant acceleration.At time t = 5.0 s its velocity is 8.0 m/s in the forward direction,and at time t = 8.0 s its velocity is 12.0 m/s forward.What is the distance traveled in that interval of time?
A)10 m
B)20 m
C)30 m
D)40 m
E)50 m

Question

Quizplus · Accepted Answer

Using the equation for average velocity 
v_avg = (v_i + v_f)/2

where v_i and v_f are the initial and final velocities respectively,

We can find the acceleration of the car as

a = (v_f - v_i)/(t_f - t_i) 
a = (12 - 8)/(8 - 5) = 4/3 m/s^2

Using the equation for distance traveled 
s = v_i*t + (1/2)*a*t^2

where s is the distance traveled, t is the time interval, and v_i is the initial velocity,

We can find the distance traveled by the car in the given time interval as

s = (8*3) + (1/2)*(4/3)*3^2 = 24 + 4 = 28 m

Therefore, the best choice is C.

A Car Is Moving with a Constant Acceleration