Question #8284d

1 Answer
Jan 27, 2018

4.0 m/s

Explanation:

Use the kinematic equations or use the definitions of acceleration and velocity to derive the kinematic equation blow.

A) Deltax= v_0t+1/2at^2
v_0= 0 larrstarting from rest, and the clock is reset to zero.

t = sqrt((2Deltax)/a)= 4.0 hrs

The answer is assuming that a = (3km)/(hr^2 because the time unit is left blank in the question.

B.) Derive the equation from the de
a = (dv)/dt and v= dx/dt

Given the a = constant and initially t=0, v(0)=v_0, x(0)=x_0
From a = (dv)/dt, and take the antiderivative,
int_(0)^tadt= v - v_0

rArrv= v_0 + at
Because v=(dx)/dt
rArr dx/dt= v_0 + at
Take the antiderivative to get
Deltax =v_0t + 1/2at^2
which is just the kinematic equation used above.