An elevator car has a mass of 1600 kg and is carrying passengers having a combined mass of 200 kg. A constant friction force of 4000 N retards its motion upward, as shown in Figure 7(a). (A) What power delivered by the motor is required to lift the elevator car at a constant speed of 3.0 m/s? (B) What power must the motor deliver at the instant the speed of the elevator is v if the motor is designed to provide the elevator car with an upward acceleration of 1.0 m/s® 3 - Fig. 7. (a) The motor exerts an upward force T on the Elevator ca. b) The free-body diagram for th elevator ca

A block of mass 2.40 kg is placed against a horizontal spring of constant k = 825 N/m and pushed so the spring compresses by 0.0750 m. HINT (a) What is the elastic potential energy of the block-spring system (in J)? (b) If the block is now released and the surface is frictionless, calculate the block's speed (in m/s) after leaving the spring. m/s

A block of mass m:=4 kg is placed on an inclined plane with angle a-35°, connected to a second hanging block of mass m_2 by a cord passing over a small frictionless pulley. The static and kinetic friction coefficients are \mu_s=0.5 and \mu_k=0.3, respectively. a.- Determine the mass m_2 such that the block m_1 rises along the plane with constant speed once set in motion. 1.35 kg B: 1.31 kg 1.52 kg B: C: 0.65 kg 1.17 kg b.- Determine the mass m1 such that the block mi moves down the plane with constant speed once set in motion. D: 0.92 kg 1.61 kg D: E: 1.54 kg E: 3.28 kg 2.15 kg c. In what range of values of m2 do the blocks remain at rest, if they are released from rest? A 0.25 kgs my s1.36 B: 0.65 kg smis 3.93 C 0.13 kgs mas 1.87 D: 0.43 kg smis 2.23 E: 0.35 kg s mis 3.87 kg kg kg kg

Please answer with full solutions