Question

What is the speed of a 200-kilogram car that is driving with 2000 joules of kinetic energy? (SHOW ALL WORK)

Answer 1

Answer:

v ≈ 4.47

Explanation:

The Formula needed = KE = $\frac{1}{2}$ m v²

Substitute with numbers known:

2000J = $\frac{1}{2}$ × 200kg × v²

Simplify:

÷100       ÷100      (Divide by 100 on both sides)

2000J = 100 × v²

$\frac{2000J}{100}$ =  v²

20 = v²

√         √             (Square root on both sides)

√20 = √v²

4.472135955 = v (Round to whatever the question asks)

v ≈ 4.47       (I rounded to 2 decimal places or 3 significant figures, as that is what it usually is)