做匀加速直线运动的物体,速度从0增大到v,动能增加了ΔEk1,速度从v增大到2v,动能增加了ΔEk2,则
A,ΔEk1:ΔEk2=1:1
B,ΔEk1:ΔEk2=1:2
C,ΔEk1:ΔEk2=1:3
d,ΔEk1:ΔEk2=1:4