m = mass of the particle = 0.5 kg
v₀ = initial velocity of the particle = (98 Cos60) i + (98 Sin60) j = 49 i + 84.87 j
a = acceleration = 0 i - 9.8 j
v = final velocity = ?
t = time of travel = 10 sec
final velocity using the kinematics equation is given as
v = v₀ + at
v = (49 i + 84.87 j ) + (0 i - 9.8 j ) (10)
v = 49 i -13.13 j
change in momentum is given as
ΔP = m (v - v₀)
ΔP = (0.5) ((49 i -13.13 j) - (49 i + 84.87 j))
ΔP = (0.5) (- 98) j
ΔP = - 49 j
magnitude of change in momentum : = 49