(1)①光路图如图所示.
②需要测量入射角i和折射角r;
③n=
sini
sinγ ;
(2)①由图示游标卡尺可得,主尺示数为5.5cm,游标尺示数为5=0×0.1mm=0.00cm,
宽度d=5.5cm+0.00cm=5.50cm;
②v 1=
d
t 1 =
5.50×0.01m
2.0×1 0 -2 s =2.75m/s ;
v 2=
d
t 2 =
5.50×0.01m
5.0×1 0 -2 s =1.10m/s ;
③根据动能定理,有:- μmgL=
1
2 m
v 22 -
1
2 m
v 21 ;
解得:μ=
v 21 -
v 22
2gL
故答案为:(1)①②如图所示;③
sini
sinγ .
(2)①5.50cm;②2.75m/s,1.10m/s;③
v 21 -
v 22
2gL .