[求助]老哥们，帮我看下大学物理这题，有法王，已解答，感谢

[img]https://img.nga.178.com/attachments/mon_202007/12/-7Q5-b1gcK2bT3cSu0-xf.jpg.medium.jpg[/img][img]https://img.nga.178.com/attachments/mon_202007/12/-7Q5-ffvyKyT3cSsg-6l.jpg.medium.jpg[/img]
[s:ac:瞎][s:ac:瞎][s:ac:瞎]
没色图不知道能不能钓到解答