(1)由动能定理得
(mg+qE)h-μ(mg+qE)cos37^0*h/sin37^0=1/2mvb^2
v=2.4m/s
(2)(mg+qE)R(1-cos37^0)=1/2mvc^2-1/2mvb^2
N-(mg+qE)=mvc^2/R
N=9.44N
(1)由动能定理得
(mg+qE)h-μ(mg+qE)cos37^0*h/sin37^0=1/2mvb^2
v=2.4m/s
(2)(mg+qE)R(1-cos37^0)=1/2mvc^2-1/2mvb^2
N-(mg+qE)=mvc^2/R
N=9.44N