Question

Is

A 0.155 kg arrow is shot upward
at 31.4 m/s. What is its kinetic
energy (KE) when it is 30.0 m
above the ground?

Answer 1

The answer is 30.8 (J)

Step-by-step explanation:

You're welcome

Answer 2

Kinetic energy = 29.912 J

Further explanation

Given

mass = 0.155 kg

vo=initial velocity = 31.4 m/s

h/d=30 m

Required

KE=kinetic energy

Solution

vt²=vo²-2ad⇒vt=final velocity

vt²=31.4²-2.10.30⇒g=10 m/s²

vt²=985.96-600

vt²=385.96 m/s

Kinetic energy (KE)

`\tt KE=(1)/(2)mv^2\\\\KE=(1)/(2)* 0.155.* 385.96\\\\KE=29.912~J`