200k views
5 votes
A child and sled with a combined mass of 50.0 kg slide down a frictionless slope. if the sled starts from rest and has a speed of 4.00 m/s at the bottom, what is the height of the hill? m

2 Answers

5 votes
Using conservation of energy

Potential Energy (Before) = Kinetic Energy (After)

mgh = 0.5mv^2

divide both sides by m

gh = 0.5v^2

h = (0.5V^2)/g

h = (0.5*2.2^2)/9.81

h = 0.25m

User Redreinard
by
6.9k points
5 votes

Answer:

The height of the hill is 0.81 m

Step-by-step explanation:

It is given that,

Mass of child and sled, m = 50 kg

The sled starts from rest and has a speed of v = 4 m/s

We have to find the height of the hill. It can be calculated using conservation of energy. The potential energy at the bottom of hill is 0 and at maximum height the kinetic energy is 0.

So,
(1)/(2)mv^2=mgh


h=(v^2)/(2g)


h=((4\ m/s)^2)/(2* 9.8\ m/s^2)

h = 0.81 m

So, the height of the hill is 0.81 m. Hence, this is the required solution.

User Eduardo Molteni
by
6.5k points