Question

A car 'A' of mass 1500kg is travelling at 25m/s collides with another car 'A' of mass 1000 kg travelling at 15m/s in the same direction. After collision of car 'A' become 20m/s . Calculate velocity of car 'A' after collision!

Answer 1

Heya friend,

Here is the answer-

Note-

m=mass
u=initial velocity
v= final velocity


Now,

m1= 1500kg
m2=1000kg
u1=25m/s
u2=15m/s
v1=20m/s
v2=?

Formula

m1u1+m2u2= m1v1+m2+v2
1500*25+1000*15= 1500*20+1000*v2
37500+15000=30000+1000v2
52500=30000+1000v2
52500-3000=1000v2
22500=1000v2
22500/1000=v2
v2= 22.5m/s


Thus, velocity of car 'B' after collision is 22.5m/s.


Hope it helps.!!!! ^_^

Answer 2

Hi !


Let ,
mass = m
initial velocity = u
final velocity = v

here ,

m₁= 1500 kg
m₂=1000 kg

u₁ = 25 m/s
u₂ = 15 m/s

v₁ = 20 m/s

we have to find v₂ !!
v₂  is the velocity after collision 

Here is a formula relating the values given ,

m₁u₁+m₂u₂ =  m₁v₁ + m₂+v₂

m₁u₁+m₂u₂ = 1500 × 25  + 1000 ×15
                    = 37500 + 15000  
                     = 52500
 
m₁v₁ + m₂+v₂  = 1500 × 20 + 1000 × v₂

                      = 30000 + 1000v₂

m₁u₁+m₂u₂ =  m₁v₁ + m₂+v₂

52500 = 3000 + 1000v₂
1000v₂ = 52500 - 30000
1000 v₂ = 22500
v₂ = 22500/1000
    = 22.5 m/s

Thus, velocity of car 'B' after collision is 22.5m/s.