# Problem: Which of the following objects has the greatest kinetic energy?(a) a 500-kg motorcycle moving at 100 km/h (b) a 1,000-kg car moving at 50 km/h(c) a 1500-kg car moving at 30 km/h (d) a 5000 kg truck moving at 10 km/h (e) a 10,000-kg truck moving at 5 km/h

###### FREE Expert Solution

Kinetic Energy (K.E.)

$\overline{){\mathbf{K}}{\mathbf{.}}{\mathbf{E}}{\mathbf{.}}{\mathbf{=}}\frac{\mathbf{1}}{\mathbf{2}}{\mathbf{m}}{{\mathbf{v}}}^{{\mathbf{2}}}}$

Ekinetic energy = J
m = mass, in kg
v = velocity of the e- = m/s

(a) a 500-kg motorcycle moving at 100 km/h

$\frac{\mathbf{k}\mathbf{g}\mathbf{·}{\mathbf{m}}^{\mathbf{2}}}{{\mathbf{s}}^{\mathbf{2}}}{\mathbf{=}}{\mathbit{J}}$

K. E. = 385802 J

(b) a 1,000-kg car moving at 50 km/h

$\frac{\mathbf{k}\mathbf{g}\mathbf{·}{\mathbf{m}}^{\mathbf{2}}}{{\mathbf{s}}^{\mathbf{2}}}{\mathbf{=}}{\mathbit{J}}$

K. E. = 192901 J

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###### Problem Details

Which of the following objects has the greatest kinetic energy?

(a) a 500-kg motorcycle moving at 100 km/h

(b) a 1,000-kg car moving at 50 km/h

(c) a 1500-kg car moving at 30 km/h

(d) a 5000 kg truck moving at 10 km/h

(e) a 10,000-kg truck moving at 5 km/h