Definition of Work When the Angle Between a Constant Force and the Displacement Is o W - (F cos B)d - F cost 7-3 SI unit: joule, J Of course, in the case where the force is in the direction of motion, the angle & is zero then W = Fd cos 0 = Fd - 1 = Fd, in agreement with Equation 7-1. The component of force in the direction of displacement is Foos d. This is the only component of the force that does work. F F coso CO F cos The work in this case is W = (F cos old. FIGURE 7-3 Work: force at an angle to the direction of motion A person pulls a suitcase with a strap at an angle # to the direction of motion. The component of force in the direction of notion is Fcos #, and the work done by the person is W - (F cos eld.Question 13 (1 point) Retake question A 840-kg elevator is lifted at a constant speed of 1.0 m/s through a height of 23.0 m. How much work is done by gravity, in kilojoules? Use the definition of work (Eq. 7-3). What is the angle between the force of gravity and the displacement? Remember to convert your answer from joules to kilojoules