Question

1. Someone fires a 0.04 kg bullet at a block of wood that has a mass of 0.5 kg. (The block of wood is sitting on a frictionless surface, so it moves freely when the bullet hits it). The wood block is initially at rest. The bullet is traveling 300 m/s when it hits the wood block and sticks inside it. Now the bullet and the wood block move together as one object. How fast are they traveling?
2. Two kids are roller skating. Amy, with a mass of 55 kg, is traveling forward at 3 m/s. Jenny, who has a mass of 40 kg, is traveling in the opposite direction at 5 m/s. They crash into each other and hold onto each other so that they move as one mass. How fast are they traveling?
3. Jake is bowling with a 8 kg bowling ball. He rolls the ball at 7 m/s, and it hits one stationary pin with a mass of 2 kg. The pin goes flying forward at 12 m/s. How fast is the bowling ball now traveling?
4. John has to hit a bottle with a ball to win a prize. He throws a 0.4 kg ball with a velocity of 18 m/s. It hits a 0.2 kg bottle, and the bottle flies forward at 25 m/s. How fast is the ball traveling after hitting the bottle?

Answer 1

C my attachment. anyway u should post only 1 math at a time. plz post ur rest of maths again

Answer 2

Since momentum is a vector quantity, take any direction as positive and other as negative. Answer won't change.