Chapter 14, Problem 49P

A two-engine jet transport has a loaded weight of 71000 lb and a forward thrust of 9800 lb per engine during takeoff. If the transport requires 4080 ft of level runway starting from rest to become airborne at a speed of 144 knots (1 knot = 1.151 mi/hr), determine the average resistance R to motion over the runway length due to drag (air resistance) and mechanical retardation by the landing gear. Answer R = i lb

At A, a 90-kg container begins at rest. When the cable is exposed to a continuous force of F-450N, determine its speed when it reaches point B. Also, what is the constant force if the speed of crate A is 7.5 m/s when passing through crate B? Neglect friction and the size of the pulley.

A constant force of ''F'' acts on a mass as shown. The mass starts its motion from rest at position 1, the unstretched length of the spring is 250 mm, and the spring modulus is k=1,5 k?/m. Neglecting the friction, determine the required force ''F'' to cause the 2−kg mass to have a speed of v2=1,5 m/s at position 2.

A toboggan having a mass of 12 kg starts from rest at A and carries a girl and boy having a mass of 40 kg and 45 kg, respectively. When the toboggan reaches the bottom of the slope at B, the boy is pushed off from the back with a horizontal velocity of vỏ/t = 2 m/s, measured relative to the toboggan. Suppose that h = 3.2 m. Neglect friction in the calculation. (Figure 1) Figure B vbil A h Part A Determine the velocity of the toboggan afterwards. Express your answer to three significant figures and include the appropriate units. Vt = Submit Value Provide Feedback Request Answer Units ?

A 8.7-Mg truck is resting on the deck of a barge which displaces 235 Mg and is at rest in still water. If the truck starts and drives toward the bow at a speed relative to the barge vrel = 7.5 km/h, calculate the speed v of the barge. The resistance to the motion of the barge through the water is negligible at low speeds.

Determine the constant force F which must be applied to the cord in order to cause the 45-lb block A to have a speed of 15 ft/s when it has been displaced 5 ft upward starting from rest. Neglect the weight of the pulleys and cord.

2. The 50 kg crate is subjected to the forces shown. If it is originally at rest, determine the distance it slides in order to attain a speed of v= 10 m/s. The coefficient of kinetic friction between the crate and the surface is 0.3. 300 N 600 N 40° 300

A sailboat weighing 980 lb with its occupants is running down wind at 8 mi/h when its spinnaker is raised to increase its speed. Determine the net force provided by the spinnaker over the 10-s interval that it takes for the boat to reach a speed of 12 mi/h.

A 9.6-Mg truck is resting on the deck of a barge which displaces 206 Mg and is at rest in still water. If the truck starts and drives toward the bow at a speed relative to the barge vrel = 9.7 km/h, calculate the speed v of the barge. The resistance to the motion of the barge through the water is negligible at low speeds. l'rel = 9.7 km/h 9.6 Mg 206 Mg- Answer: v = i km/h