15.如圖所示,一傾角θ=37°的斜面底端與一傳送帶左端相連于B點(diǎn),傳送帶以v=6m/s的速度順時(shí)針轉(zhuǎn)動(dòng),有一小物塊從斜面頂端點(diǎn)以υ
0=4m/s的初速度沿斜面下滑,當(dāng)物塊滑到斜面的底端點(diǎn)時(shí)速度恰好為零,然后在傳送帶的帶動(dòng)下,運(yùn)動(dòng)到C點(diǎn).已知斜面AB長(zhǎng)度為L(zhǎng)
1=8m,傳送帶BC長(zhǎng)度為L(zhǎng)
2=18m,物塊與傳送帶之間的動(dòng)摩擦因數(shù)μ
2=0.3,(sin37°=0.6,cos37°=0.8,g=10m/s
2).
(1)求物塊與斜面之間的動(dòng)摩擦因數(shù)μ
1;
(2)求物塊在傳送帶上運(yùn)動(dòng)時(shí)間.