Two air track carts move forward one another on an air trackcart 1 has a mass of
ID: 1681177 • Letter: T
Question
Two air track carts move forward one another on an air trackcart 1 has a mass of 0.45kg and a speed of 1.1m/s. Cart 2 has amass of 0.65kg. (a) What speed must cart 2 have if the total momentum of thesystem is to be zero? (b) Since the momentum of the system is zero, does it followthat the kinetic energy of the system is also zero? (c) Verify your answer to part (b) by calculating the systemkinetic energy. Two air track carts move forward one another on an air trackcart 1 has a mass of 0.45kg and a speed of 1.1m/s. Cart 2 has amass of 0.65kg. (a) What speed must cart 2 have if the total momentum of thesystem is to be zero? (b) Since the momentum of the system is zero, does it followthat the kinetic energy of the system is also zero? (c) Verify your answer to part (b) by calculating the systemkinetic energy.Explanation / Answer
Two air track carts move forward one another on an air track cart 1has a mass of 0.45kg and a speed of 1.1m/s. Cart 2 has a mass of0.65kg. a) now here, for momentum to be equal, we have m1v1 = m2v2 0.45 x 1.1 = 0.65 x v2 so v2 = 0.761 m/s in the opposite direction from the previousone. b) now here we see that the monemtum of the system is zero, this does not necessarily mean that , the kinetic energy is zero itcan be non zero also. it is because as the momentum is having direction the K.E is nothaving the direction . it is independent of that. c) now, here we have, K.E of the two systems =1/2 m1v12 +1/2 m2v22 = 1/2(0.45 x1.1 2 + 0.65 x 0.7612 ) =1/2 * 0.920 J = 0.46 J so this shows that the K.E is not zero as per calculation.