Answer:
70.6 mph
Explanation:
Car A mass= 1515 lb
Car B mass=1125 lb
Speed of car B is 46 miles/h
Distance before locking, d=19.5 ft
Coefficient of kinetic friction is 0.75
Initial momentum of car B=mv where m is mass and v is velocity in ft/s
46 mph*1.46667=67.4666668 ft/s
Initial momentum of car A is given by
where
is velocity of A
Taking East as positive and west as negative then the sum of initial momentum is
The common velocity is represented as hence after collision, the final momentum is
From the law of conservation of linear momentum, sum of initial and final momentum equals each other hence
The acceleration of two cars
From kinematic equation
hence
Substituting the value of in equation