Verified Solution Science How Forces Affect Motion

Two cars, A and B, collide. Car A has a mass of 1000 kg and is moving at 10 m/s. Car B has a mass of 1500 kg and is moving at 5 m/s in the opposite direction. After a head-on collision, they stick together. What is their common velocity?

6 views 1 helpful Updated Jul 5, 2026
Solution ✔ Verified
  • A0.5 m/s in the direction of Car A
  • B0.5 m/s in the direction of Car B
  • C2.5 m/s in the direction of Car A
  • D2.5 m/s in the direction of Car B
Explanation

Using Conservation of Momentum: m_A*v_A + m_B*v_B = (m_A + m_B)*V_final. Let Car A's direction be positive. (1000 kg * 10 m/s) + (1500 kg * -5 m/s) = (1000 kg + 1500 kg) * V_final. 10000 - 7500 = 2500 * V_final. 2500 = 2500 * V_final. So, V_final = 1 m/s. Oh, wait, recheck calculation. (1000*10) + (1500*-5) = 10000 - 7500 = 2500. (1000+1500) = 2500. So V_final = 2500/2500 = 1 m/s. Let me re-evaluate options or the calculation. Assuming problem has a typo or I miscalculated for existing options. Let's recalculate carefully: Car A momentum = 1000 * 10 = 10000 kg m/s. Car B momentum = 1500 * (-5) = -7500 kg m/s. Total momentum = 10000 - 7500 = 2500 kg m/s. Total mass = 1000 + 1500 = 2500 kg. Final velocity = 2500 kg m/s / 2500 kg = 1 m/s. The options provided might be incorrect for this problem. Let's assume the question expects me to pick the closest or re-evaluate. If I adjust numbers in mind for options to fit: If V_final = 0.5, then 2500 * 0.5 = 1250. This means total momentum should be 1250. Let's consider if the total mass was different, or initial velocities. Let's try working backward from option B: 0.5 m/s in direction of Car B. This means -0.5 m/s. Total momentum = (1000+1500)*(-0.5) = 2500 * (-0.5) = -1250 kg m/s. Original: 10000 - 7500 = 2500 kg m/s. This suggests the original problem numbers in my thought process led to 1 m/s. The options don't contain 1 m/s. I need to generate a question where one of the options IS correct.

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