Question

A body of mass 3.0kg and a body B of mass 10 kg are dropped simultaneously from a height of 9m.Calculate their Momenta, their Potential energies and kinetic energies when they are 10m above the ground.​

Answer 1

Answer:

momentum of object a = 40.23 kg m/s

                        object b = 134.1 kg m/s

Explanation:

formula = PE = mgh

m = mass

g = gravity

h = height

OBJECT A :

m = 3 kg

g = 10 m/s²

h = 9m

mgh = 3 kg × 10 × 9

= 270 J

OBJECT B :

m = 10 kg

g = 10 m/s²

h = 9m

mgh = 10kg × 10 × 9

= 900 J

formula = KE = 1/2 × m × v²

OBJECT A :

KE = 1/2 × m × v²

270 = 1/2 × 3 × v²

270/3 = 0.5 × v²

90 = 0.5 × v²

180 = v²

v = 13.41

OBJECT B :

KE = 1/2 × m × v²

900 = 1/2 × 10 × v²

900 = 5 × v²

180 = v²

v = 13.41

finding momentum :

formula = m × v = momentum

OBJECT A :

3 × 13.41 = 40.23 kg m/s

OBJECT B :

10 × 13.41 = 134.1 kg m/s