问题
填空题
甲、乙两同学体重之比为4:5,都从一楼走到三楼,甲和乙所用的时间之比为7:8,那么甲和乙做功之比为______,功率之比为______
答案
∵W甲=G甲h=4h,W乙=G乙h=5h;
∴
=W甲 W乙
=4h 5h 4 5
又∵P甲=
= W甲 t甲
P乙=4h 7s
=W乙 t乙
;5h 8s
∴
=P甲 P乙
×4h 7s
=8s 5h 32 35
故答案为:4:5,32:35.