Engineering Mechanics: Dynamics (14th Edition)
14th Edition
ISBN: 9780133915389
Author: Russell C. Hibbeler
Publisher: PEARSON
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Chapter 14.4, Problem 60P
If the escalator in Prob.14-46 is not moving, determine the constant speed at which a man having a mass of 80 kg must walk up the steps to generate 100 W of power-the same amount that is needed to power a standard light bulb.
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Chapter 14 Solutions
Engineering Mechanics: Dynamics (14th Edition)
Ch. 14.3 - Determine the work of the force when it displaces...Ch. 14.3 - Determine the kinetic energy of the 10-kg block.Ch. 14.3 - The spring is placed between the wall and the...Ch. 14.3 - If the motor exerts a constant force of 300 N on...Ch. 14.3 - The crate is initially at rest on the ground.Ch. 14.3 - If the drag force of the parachute can be...Ch. 14.3 - When s = 0.5 m, the spring is unstretched and the...Ch. 14.3 - The 5-lb collar is pulled by a cord that passes...Ch. 14.3 - The 20-kg crate is subjected to a force having a...Ch. 14.3 - If the relation between the force and deflection...
Ch. 14.3 - If it is originally at rest, determine the...Ch. 14.3 - If it is originally at rest, determine the...Ch. 14.3 - Determine the required height h of the roller...Ch. 14.3 - How far will the truck skid if it is traveling 80...Ch. 14.3 - Show that this is so, by considering the 10-kg...Ch. 14.3 - A force of F = 250 N is applied to the end at B....Ch. 14.3 - If the block has a mass of 20 kg and is suspended...Ch. 14.3 - Determine how far the block must slide before its...Ch. 14.3 - If the 6-kg collar is orginally at rest, determine...Ch. 14.3 - Select the proper value of k so that the maximum...Ch. 14.3 - Determine the speed of the brick just before it...Ch. 14.3 - Determine the speed of block A after it moves 5 ft...Ch. 14.3 - If the kinetic coefficient of friction between the...Ch. 14.3 - Determine the angle at which the box leaves the...Ch. 14.3 - If the cord is subjected to a constant force of F=...Ch. 14.3 - Determine the maximum distance A will fall before...Ch. 14.3 - If the cord is subjected to a constant force of F=...Ch. 14.3 - The barrier stopping force is measured versus the...Ch. 14.3 - The coefficient of kinetic friction between both...Ch. 14.3 - If the coefficient of kinetic friction between the...Ch. 14.3 - The 8-Kg block is moving with an initial speed of...Ch. 14.3 - At a given instant the 10-lb block A is moving...Ch. 14.3 - The 5-lb cylinder is falling from A with a speed...Ch. 14.3 - The propelling action is obtained by drawing the...Ch. 14.3 - By design the car cannot fall off the track,...Ch. 14.3 - If the coefficient of kinetic friction along AB is...Ch. 14.3 - Prob. 29PCh. 14.3 - If the can is prevented from moving, determine the...Ch. 14.3 - Determine the placement R of the can from the end...Ch. 14.3 - If it starts from rest when the attached spring is...Ch. 14.3 - Neglect the size of the block.Ch. 14.3 - As shown, the spring is confined by the plate P...Ch. 14.3 - Determine his speed when he reaches point B on the...Ch. 14.3 - As shown, it is confined by the plate and wall...Ch. 14.3 - If the track is to be designed so that the...Ch. 14.3 - Neglect friction.Ch. 14.3 - Neglect friction and the size of the pulley.Ch. 14.3 - Neglect friction and the size of the pulley.Ch. 14.3 - An elastic cord having a stiffness k = 2 lb/ft is...Ch. 14.4 - In initially, the block is at rest.Ch. 14.4 - When s = 0, the 20-kg block is moving at v = 1...Ch. 14.4 - The load weighs 100 lb and the efficiency of the...Ch. 14.4 - If the block is traveling up the inclined plane...Ch. 14.4 - determine the power input to the motor, which...Ch. 14.4 - which is increasing at a rate of aP = 6 m/s2....Ch. 14.4 - Assuming the wheels do not slip on the ground,...Ch. 14.4 - Determine the power Input for a motor necessary to...Ch. 14.4 - If mechanical friction and wind resistance are...Ch. 14.4 - manufactures a turbojet engine that is placed in a...Ch. 14.4 - If the car is brought to a stop, determine how...Ch. 14.4 - If the steps are 125 mm high and 250 mm in length,...Ch. 14.4 - Determine the power generated. How long would a...Ch. 14.4 - Determine the maximum power that must be supplied...Ch. 14.4 - The cable is tied to the top of the oil rig, wraps...Ch. 14.4 - The motor has an efficiency of = 0.65.Ch. 14.4 - The 50-lb crate is given a speed of 10ft/s in t =...Ch. 14.4 - The engine has a running efficiency = 0.68.Ch. 14.4 - If the drag resistance on the car due to the wind...Ch. 14.4 - Hoisting is provided by the motor M and the 60-kg...Ch. 14.4 - If the rod is smooth, determine the power...Ch. 14.4 - Determine the power developed by the power...Ch. 14.4 - A force F = (40 + s2) lb, where sis in ft, acts on...Ch. 14.4 - If the steps are 125 mm high and 250 mm in length,...Ch. 14.4 - If the escalator in Prob.14-46 is not moving,...Ch. 14.4 - Neglect drag and rolling resistance, and the loss...Ch. 14.4 - Also, the velocity of the athletes arm acting in...Ch. 14.4 - Prob. 63PCh. 14.4 - If the motor draws in the cable at a constant rate...Ch. 14.5 - If a force F = (60t2) N, where t is in seconds, is...Ch. 14.5 - Determine the potential energy of the block that...Ch. 14.5 - Determine the potential energy in the spring that...Ch. 14.5 - The 2-kg pendulum bob is released from rest when...Ch. 14.5 - The 2-kg package leaves the conveyor belt at A...Ch. 14.5 - The 2-kg collar is given a downward velocity of 4...Ch. 14.5 - Determine the speed of the collar when it strikes...Ch. 14.5 - Determine the compression of each spring when the...Ch. 14.5 - If the guide rod is smooth, determine the speed of...Ch. 14.5 - If she is swinging to a maximum height defined by ...Ch. 14.5 - If it is then released, determine the maximum...Ch. 14.5 - Determine the speed of the collar when it reaches...Ch. 14.5 - Determine its speed when its center reaches point...Ch. 14.5 - If it is released from rest when = 0, determine...Ch. 14.5 - If the car is released from rest, determine its...Ch. 14.5 - Prob. 72PCh. 14.5 - If it is released from rest at the top of the hill...Ch. 14.5 - Determine the speed of each block when B descends...Ch. 14.5 - Determine the distance B must descend in order for...Ch. 14.5 - The spring has a stiffness k =50 N/m and an...Ch. 14.5 - Neglect friction.Ch. 14.5 - If it is attached to the 3-kg smooth collar and...Ch. 14.5 - Prob. 79PCh. 14.5 - If the arm is pulled back such that s = 100 mm and...Ch. 14.5 - If the arm is pulled back such that s = 100 mm and...Ch. 14.5 - For the calculation, locate the datum at r . Also,...Ch. 14.5 - Prob. 83PCh. 14.5 - The spring has an unstretched length of 1 m.Ch. 14.5 - A 60-kg satellite travels in free flight along an...Ch. 14.5 - If friction and air resistance can be neglected,...Ch. 14.5 - If the mass of the bumpers A and B can be...Ch. 14.5 - If the collar moves over the smooth rod, determine...Ch. 14.5 - When the 6-kg box reaches point A it has a speed...Ch. 14.5 - Determine the normal force the box exerts on the...Ch. 14.5 - Determine how high the box reaches up the surface...Ch. 14.5 - Determine the cars velocity and the normal force...Ch. 14.5 - The 10-kg sphere C is released from rest when =...Ch. 14.5 - If the chain is released from rest from the...Ch. 14.5 - Each spring has a stiffness k = 40 N/m and an...Ch. 14.5 - Prob. 96PCh. 14.5 - Initially each spring has a tension of 50 NCh. 14.5 - Determine the approximate normal force it exerts...Ch. 14.5 - If a 150-lb crate is released from rest at A,...Ch. 14.5 - During the motion, the collar is acted upon by a...Ch. 14.5 - Determine the speed at which it slides off at B....Ch. 14.5 - If the block starts from rest when the attached...Ch. 14.5 - Prob. 5RPCh. 14.5 - The motor has an efficiency of = 0.76.Ch. 14.5 - If the collar is released from rest at A and...Ch. 14.5 - respectively. They are connected together by a...
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- Determine the force necessary to accelerate a mass of 20 lbm at a rate of 60 ft/sec2 vertically upward.arrow_forwardDetermine the power input for a motor necessary to lift 280 lb at a constant rate of 6 ft/s. The efficiency of the motor is ϵ = 0.65. Express your answer with the appropriate units.arrow_forward2. The 200 gram toy car will be compressed against the spring and released to send it around the loop which has diameter of 60 cm. Determine minimum required spring compression to maintain contact with the track for the entire loop. First use kinetics to determine minimum velocity at the top of the track, and then apply conservation of energy. Spring constant is 400 N/m. -------arrow_forward
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