A trolley of mass 300kg carrying a sand bag of 25kg is moving uniformly with speed of 27km/h on a frictionless track. After a while, sand starts leaking out of a hole on the floor of the trolley at the rate of 0.05 kg/s.
What is the speed of the trolley after the entire sand bag is empty?
I was so surprised when I read this question. It doesn't make sense to me. I can't comprehend how the loss of sand creates an external unbalanced force on the trolley such that it affects its velocity.
Maybe I haven't analyzed the question enough but I find this a bit conceptually challenging for me. Maybe I have to consider how the sand particles affect the back wheels of the trolley or maybe consider the sand to be a propellant?