1. The problem statement, all variables and given/known data When a car is accelerating with a pendulum hanging inside it, then why does the pendulum get aligned with the vertical at an angle? Can you explain it without using the concept of pseudo force? I tried it but I was not able to get it. 3. The attempt at a solution My Attempt: According to what has been taught in the class, for determining which way the pendulum gets aligned, we assume any one direction and then resolve the tension force in the string in 2 directions. One along the motion of the car and the other upward, towards the roof of the car. Using the horizontal direction force we can judge which way the pendulum should actually align using Newton's Second Law of Motion F is proportional to a (acceleration). But following this the pendulum should align in the forward direction, i.e the right direction if the car is accelerating towards right. But its the opposite, i.e the pendulum aligns leftwards and not rightwards. Can anyone explain why this happens?