Work energy power

Question - Describe how the measurements would be used to investigate the conservation of energy?
I know that, we should find out the masses of the trolley and mass, Need to find MGH so need to find out the distance between the ground and them mass, and KE can be calculated before that need to find V, which can be calculated using the distance and time taken to fall. But is there anything to do with the trolley? The mark scheme says, need to find the speed of the trolley and KE as well, whats the link right there? I am confused. Please explain the conservation of energy of this experiment.
And Any Idea about how the graphs will be? will It be a curve or a straight line?

For energy to be fully conserved, all of the gravitational potential energy in the system at the start, must be converted to kinetic energy at the end:

$mgh = \frac{1}{2}mv^{2}$

with no energy losses.

since trolley is loosing ke and the mass is gaining KE would it be equal and since mass is loosing gpe and gaining ke. would that be equal to? confused.

The mass of both the trolley and the suspended weight will provide the gpe.

They are both stationary at the start of the experiment.

They then both accelerate under gravity so both must accrue kinetic energy as the gpe converts.

At the start the energy in the system must all be potential. At the end, there is no more potential and everything is converted to kinetic.

okay i understood! okay so far what it seems like the loosing KE of the trolley converts gpe of the suspended weight to KE. wil the loss of KE of the trolley equal to gain of KE of the suspeneded mass?

?????

The trolley does not lose KE. It gains KE.

The trolley converts it's own gpe to KE.

The weight does not lose KE. It gains KE.

The weight converts it's own gpe to KE.


The weight is pulling the trolley !

Effectively, the mass of the trolley and the mass of the weight are summed.

They both move the same distance at the same time. The weight falls vertically and the trolley moves horizontally.