MPLE 14.6 Blocks A and B shown in Fig. 14-14a have a mass of 10 kg and 100 kg. respectively. Determine the distance B travels when it is released from rest to the point where its speed becomes 2 m/s. Datum SOLUTION This problem may be solved by considering the blocks separately and applying the principle of work and energy to each block. However, the work of the (unknown) cable tension can be eliminated from the analysis by considering blocks A and B together as a single system. 100 kg A10 kg (a)

As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff ideal springs arranged side by side so that they are parallel to each other. When you push the platform, you compress the springs. You do 75.0 J of work when you compress the springs 0.220 m from their uncompressed length. a) What magnitude of force must you apply to hold the platform in this position? b) How much additional work must you do to move the platform 0.220 m farther?  c) What maximum force must you apply to move the platform to the position in Part B?

A woman places a 2 kg block against a horizontal spring of force constant K = 300 N/m and compresses it 9 cm. a) Find the work done by the woman and the work done by the spring.b) The block is released and leaves the spring when the spring is at its original position. Find the speed of the block when it leaves the spring.

As a segment of an workout regiment to toughen their pectoral muscles, a man stretches a spring which has a spring constant k=605N/m. a) If x=0 corresponds to when the springs are at their relaxed state, which image best represents the magnitude of the force applied to the springs as a function of the stretch distance (see image). b) Write an equation for the work necessary to stretch the spring from the relaxed state to a distance x1. c) Calculate the work, in joules, required to stretch the spring from its relaxed state to the position x1=59.7cm d) Write an equation for the work necessary to stretch the spring from the position x1 to position x2. e)  Calculate the work, in joules, required to stretch the spring from x1=59.7cm to x2=96.8cm.

With complete solution please

Figure 9 shows four situations in which a force F is applied to an object resulting in displacement Ař. The force has the same magnitude in all four cases, but points in different directions. The displacement is exactly the same in all four cases. Which of the following choices correctly ranks the work done by the force on the object? a) W. < Wa < Wa < Wp b) Wa < Wc < W, < Wa c) Wa < Wc < Wa < Wp d) Wa < W, < Wa < Wc e) Wh < Wa < Wa < Wc Ar Δ b Ar Ar Figure 9

An uncontrolled 850 kg car strikes squarely a motorway crash cushion in which the car is brought to rest by successively crushing steel barrels. The length of the crash cushion is 5.9 m, and the magnitude F of the force required to crush the barrels as a function of the distance the car has moved into the cushion is given by  (image attached) a) Determine an expression for the work done by the force Fas a function of x b) If the car strikes the crash cushion with a velocity of 38km / h , determine the distance the car will move into the cushion before it comes to rest and the maximum deceleration of the car. c) Determine the maximum velocity with which the car can strike the cushion so that it will not hit the wall behind the cushion.

14. A coin slides over a frictionless plane and across an y coordinate system from the origin to a point with ry coordinates (3.0 m, 4.0 m) while a constant force acts on it. The force has magnitude 2.0N and is directed at a counterclockwise angle of 100 from the positive direction of the r axis. How much work is done by the force on the coin during the displacement?

A cart is pulled a distance D on a flat, horizontal surface by a constant force F that acts at an angle θ with the horizontal direction. The other forces on the object during this time are gravity ( Fw ), normal forces ( FN1 ) and ( FN2 ), and rolling frictions Fr1 and Fr2 , as shown below. What is the work done by each force?

A 2,200-kg pile driver is used to drive a steel I-beam into the ground. The pile driver falls 4.60 m before coming into contact with the top of the beam, and it drives the beam 15.0 cm farther into the ground as it comes to rest. Using energy considerations, calculate the average force the beam exerts on the pile driver while the pile driver is brought to rest. 588925.42 magnitude Write an expression for the work done by all of the forces acting on the beam as it moves into the ground and relate that work to the change in energy of the pile driver in order to find the force that the beam exerts on the pile driver. N