T101-Q-1 Figure 1 shows the spring force as a function of position x for a spring-block system resting on a frictionless table. The block is released at x = + 10 cm. How much work (in Joules) does the spring do on the block when the block moves from xi = + 8.0 cm to xf=-4 cm? +2.4 T101: Q3. A particle is acted on by a constant force F = (2.0 N)i– (5.0 N)j and is displaced from an initial position of di= (0.50 m)i+ (0.80 m)j at time t = 0 s to a final position of df= (3.5 m)i+ (9.8 m)j at time t = 10 s. Find the average power (in Watts) on the particle due to this force in this time interval. A) –3.9 T101Q4. A single force acts on a 5.0 kg object. The position of the object as a function of time is given by x = 10 t – 5.0 t2, where x is in meters and t is in seconds. Find the work done by this force on the object in the interval from t = 0 s to t = 5.0 s. A) 3.8 ×103 J T101Q5. An object of mass 1.0 kg is moving in a straight line over a rough horizontal surface. The coefficient of kinetic friction between the object and the floor is 0.20. What is the power that must be supplied to the object in order to keep it moving at a constant speed of 2.0 m/s? A) 3.9 W

T102 Q2. An elevator is designed to carry a load of 20 T102 Q2. An elevator is designed to carry a load of 20.0 × 103 N from the ground to a height of 87.5 m in a time of 18.0 seconds. What is the average power that must be supplied by the motor of the elevator to lift this load? 97.2 × 103 W T102-Q4. A block, of mass m= 200 g , slides back and forth on a frictionless surface between two springs, as shown in Figure 3. The left-hand side spring has k1= 130 N/m and its maximum compression is 16 cm. The right-hand side spring has k2= 280 N/m . Find the maximum compression of the right-hand side spring. A) 11 cm. T112: Q3. In Figure 2, a 5.0-kg block is moving at 5.0 m/s along a horizontal frictionless surface toward an ideal spring that is attached to a wall. After the block collides with the spring, the spring is compressed a maximum distance of xm. What is the speed of the block when the spring is compressed to only xm/2 ? Ans: 4.3 m/s