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 11 (1 point) Retake question A 57-kg packing crate is pulled with constant speed across a rough floor with a rope that is at an angle of 25.00 above the horizontal. If the tension in the rope is 138 how much work is done on the crate by the rope to move it 8.00 m, in joules? Use the definition of work (Eq. 7-3}. Watch for the ahgte between the applied force and the displacement