Apex

in an isolated system, two cars, each with a mass of 1,100 kg, collide. car 1 is initially at rest, while car 2 was moving at 10m/s. what is the magnitude of their combined momentum after the collision?

A

Explanation:

Momentum before = momentum after

(1,000 kg) (0 m/s) + (1,000 kg) (10 m/s) = p

10,000 kg m/s = p

Answer is A.

The answer is A.

Okey, here we need to use the conservation of momentum!

(in the text and the image the masses are different, i will use the one of the image)

the total momentum before the collision is:

P = momentum of car 1 + momentum of car 2 = 0m/s*1000 kg + 10 m/s*1000 kg.

so the initial momentum is 10000 kg*m/s.

Because the system is isolated, and we will think that there is no loss of energy because of friction or anything like that, the momentum will conservative after the collision ( in a real situation the cars will absorb some of the energy in the collision).

So using the conservation of momentum, the momentum after the collision must be the same as before, so the answer is A = 10000 kg*m/s.

the answer is b ) square root of 5

explanation:

v=uf/(u-f)

= 5.-10/(5+10) convex lens has negative focal length