When a car of mass 1167 ${~kg}$ accelerates from 10.0 m/s to some final speed, 4.00 × 10⁵ J of work are done. Find this final speed. A) 28.0 m/s B) 22.4 m/s C) 25.2 m/s D) 30.8 m/s

Question

Quizplus · Accepted Answer

The work done on the car is equal to the change in its kinetic energy:$$W = \frac{1}{2}mv_f^2 - \frac{1}{2}mv_i^2$$Solving for $v_f$, we get:$$v_f = \sqrt{\frac{2W}{m} + v_i^2}$$Plugging in the given values, we get:$$v_f = \sqrt{\frac{2(4.00 \times 10^5 \text{ J})}{1167 \text{ kg}} + (10.0 \text{ m/s})^2} = 28.0 \text{ m/s}$$

When a Car of Mass 1167 kg{~kg} kg Accelerates from 10

When a Car of Mass 1167 ${~kg}$ Accelerates from 10