A 1.9-kg object is moving at 5.5 m/s. If a force in the direction of the motion does 27.9 J of work on the object, what is the object's final speed?
A) 28.7375 m/s
B) 7.72 m/s
C) 56.6375 m/s
D) 5.46 m/s
E) 6.70 m/s

Question

Quizplus · Accepted Answer

The work done on the object results in a change in kinetic energy, which can be calculated using the work-energy principle: Work = ΔKE = 0.5 * m * (v_f^2 - v_i^2), where m is the mass, v_f is the final velocity, and v_i is the initial velocity. Rearranging for v_f gives us v_f = sqrt((2*Work/m) + v_i^2). Plugging in the given values: v_f = sqrt((2*27.9/1.9) + 5.5^2) ≈ 7.72 m/s.

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