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2 years ago

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A 16.0 kg child on roller skates, initially at rest, rolls 2.0 m down an incline at an angle of 20.0° with the horizontal. If th

ere is no friction between incline and skates, what is the kinetic energy of the child at the bottom of the incline?

1 answer:

enyata [817]2 years ago

7 0

The kinetic energy of the child at the bottom of the incline is 106.62 J.

The given parameters:

<em>Mass of the child, m = 16 kg</em>
<em>Length of the incline, L = 2 m</em>
<em>Angle of inclination, θ = 20⁰</em>

The vertical height of fall of the child from the top of the incline is calculated as;

$sin(20) = \frac{h}{2} \\\\h = 2 \times sin(20)\\\\h = 0.68 \ m$

The gravitational potential energy of the child at the top of the incline is calculated as;

$P.E = mgh\\\\P.E = 16 \times 9.8 \times 0.68\\\\P.E = 106.62 \ J$

Thus, based on the principle of conservation of mechanical energy, the kinetic energy of the child at the bottom of the incline is 106.62 J since no energy is lost to friction.

Learn more about conservation of mechanical energy here: brainly.com/question/332163

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