From conservation of linear momentum,
mv=(4m+m)vf
vf=5v
From conservation of mechanical energy,
21mv2=21(4m+m)vf2+mgh
v2=5vf2+2gh
v2=5×(5v)2+2gh
h=5g2v2
A wedge of mass M=4m lies on a frictionless plane. A particle of mass m approaches the wedge with speed v. There is no friction between the particle and the plane or between the particle and the wedge. The maximum height climbed by the particle on the wedge is given by:
Held on 9 Apr 2019 · Verified 6 Jul 2026.
gv2
2gv2
5g2v2
7g2v2
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