Question

An object with a mass of 32 kg has an initial energy of 500). At the end of the experimentthe velocity of the object is recorded as 5.1 m/s . the object travelled 50 m to get to this point, what was the average force of friction on object during the tripAssume no potential energy Show all work

Answer 1

F = 1.68 N

Step-by-step explanation:

Let's solve this exercise in parts.

Let's use the concept of conservation of the mechanical nerve

initial

Em₀ = 500 J

The energy is totally kinetic

Em₀ = K = ½ m v₀²

v₀ =
`\sqrt{(2 Em_(o) )/(m) }`

v₀ = √ (2 500/32)

v₀ = 5.59 m / s

now with kinematics we can find a space

v² = v₀² - 2 a x

the negative sign is because the body is stopping

a =
`( (v_(o)^(2) - v^(2) )/(2x) )`

let's calculate

a = (5.59² - 5.1²) / 2 50

a = 0.0524 m / s²

Finally let's use Newton's second law

F = ma

F = 32 0.0524

F = 1.68 N