A car runs a red light and broadsides Car B, which is wating to make a left turn. Car A has a mass of 2,000 kg. Car B has a mass of 1,500 kg. After the impact, the cars stick together and slide away at a speed of 9.1 m/s. How fast was Car A going when it hit Car B?

Question

A car runs a red light and broadsides Car B, which is wating to make a left turn. Car A has a mass of 2,000 kg. Car B has a mass of 1,500 kg. After the impact, the cars stick together  and slide away at a speed of 9.1 m/s. How fast was Car A going when it hit Car B?

anonymous · Answer

Use the principle of conservation of momentum. You should get 15.____

anonymous · Answer

but what is the conservation of momentum?

anonymous · Answer

momentum is mass x velocity. M1V1 = M2V2

anonymous · Answer

Initial mass is 2000. Find out what the final mass is and put in your values into the equation.

anonymous · Answer

what is the initial velocity?

anonymous · Answer

what do you know about momentum?

anonymous · Answer

nothing im sorry:(

anonymous · Answer

Wikipedia: In classical mechanics, linear momentum or translational momentum (pl. momenta; SI unit kg m/s, or equivalently, N s) is the product of the mass and velocity of an object. For example, a heavy truck moving fast has a large momentum—it takes a large and prolonged force to get the truck up to this speed, and it takes a large and prolonged force to bring it to a stop afterwards. If the truck were lighter, or moving more slowly, then it would have less momentum.

anonymous · Answer

Knowing this, conservation of momentum means that initial and final momentum is the same. Hence M1V1 = M2V2. Substitute the values. It is not hard..

anonymous · Answer

its like this 2000+9.1 m/s=1500+?

anonymous · Answer

M1V1 = M1 x V1, not M1 x V1

anonymous · Answer

not M1 + V1

anonymous · Answer

mass at the beginning is just one car, but mass at the end is two cars

anonymous · Answer

can you show me how?

anonymous · Answer

i cant do it for real. please help me