Question

answer plzz... All of these questions...

Answer 1

10) at Max height there is only horizontal component of the velocity because there no acceleration in that direction . i.e VcosƟ
consider then object has initially mass 2m .
because it exploded due to the internal forces .
i.e Fnet = 0
dp/dt = 0
dp = 0
p = constant or conserved
P initial = P final
2m(VcosƟî) = m(-VcosƟî) + m(v)
2VcosƟî = -mVcosƟî + v
v = 3VcosƟî
they asked speed i.e magnitude of the velocity
|v| = √(3VcosƟ)²
|v| = 3VcosƟ
answer :- C)
if they ask angle of that particle then it is 0° about horizontal

11) consider the object having mass 5m which is initially at rest when it exploded two object having mass
m moves perpendicular to the each other hence 3rd particle has mass 3m .
Fnet = 0
p = constant
Pi = Pf
5m(0) = m(30î) + m(30j) + 3m(v)
0 = 30î + 30j + 3v
3v = -30î - 30j
v = -10î -10j
|v| = √(-10)²+(-10)²
|v| = √200
|v| = 10√2

tanƟ = 10/10
tanƟ = 1
Ɵ = 45°

ans:- B)