Question

The following figure shows velocity –time graph for the journey of a car in 100minutes.

1. Determine the acceleration of the car between A and B and between C and D 
2. Determine the distance covered by the car during the journey 
3. Determine the average velocity of the car 

Answer 1

1. a = slope of graph
      = 30m s ⁻¹   
        30 x 60s
      = 0.016m s⁻²  
   between C and D
   a=−30m s ⁻¹  
       10 x 60s
   = 0.05m s⁻²
2. Distance = area under graph
                =30ms⁻¹ x ( 100 + 60) x 60s
                                         2
                = 144 000m.
3. V_av = total distance
               total time
         = 144 000m   
            100 x 60s
         = 24ms⁻¹