Distance / speed. So, 63/35. Answes is 1.8
Please look at the attached awesome drawing.
Both answers are there.
Explanation:
This problem bothers elastic collision.
Given data
Mass m1= 25kg
Initial velocity u1= 5m/s
Final velocity v1= 1.5m/s
Mass m2= 35kg
Initial velocity u2=?
Final velocity v2 = 4.5m/s
A. To find the initial velocity of the 35kg car, let us Apply the principle of conservation of energy
m1u1+m2u2= m1v1+m2v2
25*5+ 35*u2= 25*1.5+ 35*4.5
125+35u2= 37.5+157.5
125+35u2=195
35u2= 195-125
35u2= 70
u2= 2m/s
The initial velocity is 2m/s
B. Totally not kinetic energy before impact
KE= 1/2m1u1²+ 1/2m2u2²
KE= (25*5²)/2+ (35*2²)/2
KE= 625/2 +140/2
KE= 312.5+70
KE= 382.5J
Total kinetic energy after impact
KE=1/2m1v1²+ 1/2m2v2²
KE= (25*1.5²)/2 +(35*4.5²)/2
KE= 56.25/2 +708.75/2
KE=28.125 +354.375
KE= 382.5J
We can see that energy is conserved
Kinetic energy before and after impact remains unchanged
