A block of mass 2 kg is free to move along the x-axis. It is at rest and from t = 0 onwards it is subjected to a time-dependent force F(t) in the x direction. The force F(t) varies with t as shown in the figure. The kinetic energy of the block after 4.5 seconds is

Engineering

Physics

Momentum and Energy Conservation for System of Particles

Question

7.50J

4.50J

5.06J

14.06J

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Area = mv = $\frac{1}{2} \times 4 \times 3 - \frac{1}{2} \times 2 \times 1 .5$ = 4.5 = 2 × v

v = 2.25 m/s

$k = \frac{1}{2} \times 2 \times {(\frac{4 .5}{2})}^{2} = 5 .06 J$