Step-by-step explanation:
Given that,
Mass of the roller costar, m = 275 kg
It sits at the top of a hill with height 85 m, h = 85 m
We need to find the speed with which it is going when it reaches the bottom. It can be calculated using the conservation of energy as :
![(1)/(2)mv^2=mgh](https://img.qammunity.org/2019/formulas/physics/middle-school/klx4bqwt3gtkjbhzhlss2on2deeh3tft32.png)
g is the acceleration due to gravity
![v=√(2gh)](https://img.qammunity.org/2019/formulas/physics/middle-school/fa5ubeuru57c5ui14d6o1qi6dyaujkr9sv.png)
![v=√(2* 9.8* 85)](https://img.qammunity.org/2019/formulas/physics/middle-school/pem5sdz8z3u7u508r5jn1jdqgs82f4w834.png)
v = 40.81 m/s
So, the speed of the roller coaster when it reaches the bottom is 40.81 m/s. Hence, this is the required solution.