Question

A 2,600 kg SUV traveling west at 15 m/s collides head on with a 1,300 kg four door sedan traveling east at 20 m/s. Determine the speed and direction of the two cars immediately after impact if they lock together​.

Answer 1

Step-by-step explanation:

From Law of conservation of momentum,

m1u1+m2u2 = m1v1+m2v2 [Law of conservation of momentum]

m1 = 2600kg

u1 = 15m/s

m2 = 1300kg

u2 = -20m/s [as it is moving in opposite direction]

here, after impact, cars lock with each other so v (final velocity) is the same for both cars, i.e., v1 = v2

(2600)(15)+(1300)(-20) = (2600)v1+(1300)v2

39000-26000 = (2600+1300)v1 [as v1 = v2]

v1 = 13000/3900

v1 = 3.33 m/s

Here, m1v1 = 2600x3.33 = 8658kgm/s

m2v2 = 1300x3.33 = 4329kgm/s

As final momentum of car 1 is higher than that of car 2, both cars will move in direction of car1, that is, west direction.