Question

A 3kg stone is dropped from a height of 4m. What is its momentum as it strikes the ground? Solve using suvat

Answer 1

`"26.55 kgm/s"`

Explanation:

Velocity `("v")` when it hits the ground is

`"v"^2 = "u"^2 + "2aS"`

`"v" = sqrt("u"^2 + "2aS")`

`"v" = sqrt(("0 m/s")^2 + ("2 × 9.8 m/s"^2 × "4 m")) = "8.85 m/s"`

Momentum when it strikes the ground is

`|vec"p"| = "m"|vec"v"| = "3 kg × 8.85 m/s" = color(blue)("26.55 kgm/s")`