Answer to Question #242752 in Mechanics | Relativity for wewek

Question

a car has an initial velocity of 30m/s and an acceleration of -5 m/s². Find its displacement after 10 seconds.

Answer 1

We use the information provided and we find the displacement for a movement with linear acceleration:

$d_0=0\,m \\ a=-5\frac{m}{s^2} \\ v_i=30\frac{m}{s} \\t=10\,s \\d=d_0+v_0t+\cfrac{at^2}{2} \\d=0\,m+(30\frac{m}{s})(10\,s)+\cfrac{-5\frac{m}{s^2}(10\,s)^2}{2} \\ \implies d=0\,m+300\,m-250\,m=50\,m$

After substitution, we find that the displacement of the car after 10 seconds is about 50 m.

Reference:

• Sears, F. W., & Zemansky, M. W. (1973). University physics.