If an object with a mass of 2 kg changes speed from 3 m/s to m/s, by how much does its kinetic energy change?
1 Answer
May 14, 2016
Explanation:
Recall that the formula for kinetic energy is:
color(blue)(|bar(ul(color(white)(a/a)DeltaE_k=1/2mv^2color(white)(a/a)|))) where:
DeltaE_k= change in kinetic energy
m= mass (kilograms)
v= velocity (metres per second)
Start by breaking down
DeltaE_k=1/2mv_f^2-1/2mv_i^2
Simplify.
DeltaE_k=1/2m(v_f-v_i)^2
Substitute the given values.
DeltaE_k=1/2(2kg)(1m/s-3m/s)^2
Solve.
DeltaE_k=1/2(2kg)(4m^2/s^2)
DeltaE_k=color(green)(|bar(ul(color(white)(a/a)color(black)(4J)color(white)(a/a)|)))