A boy with a mass of 45 kg runs towards a stationary trolley with a total mass of 30 kg. The boy then jumps on the trolley and the trolley starts to move. a) Explain why the trolley starts to
move after the boy jumps on it.
b) Calculate the magnitude of the
velocity of the trolley after the boy jumps on it.

anyone here cold helps me to solve and explain the answer... thanks in advance

Mass (kg) force (n) 5 25 10 50 15 75 20 100 a student was trying to find the relationship between mass and force. he placed four different masses on a table and pulled them using a spring scale. the table shows the different masses used in the experiment and the force required to pull each mass. the student concluded that more force was required to pull heavier objects. what comment would you make regarding his conclusion? a) no clear relation can be observed between mass and force from the data. b) there is a direct proportion between the mass and force listed in the table. c) gravity should have been taken into account while performing the experiment. d) there is an inverse proportion between the mass and force listed in the table.

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j? 1. write the equation 2.list out your known variables 3.plug the numbers into the equations 4.solve 5.write your solution statement that includes initial energy and final

Sunidhi made a study chart about changes in states of matter. which headings best complete the chart?