A bus traveling at 30 km/h speeds up at a constant rate of 3.5 m/s^2. what velocity does it reach 6.8s later?

Answer 1

Use the kinematic equation of motion v_f = v_i + at where v_f is velocity final (what you are looking for), v_i is the initial velocity, a is the acceleration, and t is the time that the acceleration is occurring.

HOWEVER, the units must match. 30 km/hr x 1000 meters/km x 1 hr/3600 s = 8.333 m/s

So v_f = v_i + at

v_f = 8.333 + (3.5)(6.8) = 32.13 m/s

If you use the correct number of significant figures, since the initial velocity has only 1 sig fig, the answer should only have 1 sig fig, So in reality the correct answer should by 30 m/s