Answer:
K = 960 J
Step-by-step explanation:
Given that,
Mass of a child = 20 kg
Mass of a sled = 10 kg
Speed of child on sled = 8 m/s
We need to find the kinetic energy of the sled with the child.
The total mass of child and the sled = 20 kg + 10 kg
= 30 kg
The formula for the kinetic energy of an object is given by :
![K=(1)/(2)mv^2\\\\K=(1)/(2)* 30* (8)^2\\\\K=960\ J](https://img.qammunity.org/2022/formulas/physics/high-school/sizpx66t6xquvhwdfn69it1x02f7ju17wz.png)
Hence, the kinetic energy of the sled with the child is 960 J.