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A car (m = 1302 kg) traveling along a road begins accelerating with a constant acceleration of 1.50 m/s2 in the direction of motion. After traveling 392 m at this acceleration, its speed is 35.0 m/s. Determine the kinetic energy of the car when it began accelerating.

Respuesta :

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First we will use the concepts of motion kinetics for which the final speed is defined as shown below,

[tex]v_f^2=v_i^2+2as[/tex]

Here,

[tex]v_f[/tex]= Final velocity

[tex]v_i[/tex]= Initial velocity

a = Acceleration

s = Distance

Replacing,

[tex](35)^2 = v_i^2+2(1.5)(392)[/tex]

[tex]v_i = 7m/s[/tex]

Using the conservation of energy for kinetic energy we have,

[tex]KE = \frac{1}{2}mv_i^2[/tex]

[tex]KE = \frac{1}{2}(1302)(7)^2[/tex]

[tex]KE = 31900J[/tex]

Therefore the kinetic energy of the car is 31900J

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