Respuesta :
Answer: a= 4.4ms-2
Displacement= 26.95 m
Explanation:
First, the speed in km/hr must be converted to m/s so that we can apply it in solving the question. The motion started from rest hence the initial velocity is 0m/s. The average displacement is also obtained from the equations of motion as shown in the image attached.

Answer:
a) Average acceleration =4.44m/s^2
b)6354.20m
Explanation:
Change in speed= 72000/3600= 20m/s
Average speed= 20m/s/2=10m/s
Time to run 45m= 45/10 =4.5seconds
Average acceleration = change in speed/ time= 20/4.5=4.44m/s^2
b) V =at at t=53.5second
V = 4.44×53.5=237.54m/s
Average speed= 237.54/2=218.77m/s
Displacement= average speed×time= 118.77× 53.5
Displacement= 6354.20m