note: initial speed is 0 when starting from rest
1A)
Average speed = total distance / total time
= 12/3
= 4 m/s
1B)
average speed = (initial speed + final speed)/2
4 = (0 + v)/2
v = 8 m/s
2A)
Using
v = u + at, where v is the final speed, u is the initial speed (0 m/s), a is the acceleration (3 m/s²) and t is the time (4 s)
v = 0 + (3)(4)
v = 12 m/s
2B)
using
s = ut +0.5at² with u = 0,
s = 0.5(3)(4)²
s = 24 m
3A)
using
v = u + at, with u = 0
v = 0 + (3)(8)
v = 24 m/s
3B)
s = ut +0.5at²
s = 0.5(3)(8)²
s = 96 m
