Problem 3: Two children push horizontally on a third child who is sitting fixed in a wagon that has essentially frictionless wheels. The first child pushes in the positive x-direction with a force of magnitude 70 N while the second child pushes in the negative x-direction with a force of magnitude 95 N. a) Draw a free-body diagram of the "child-in-the-wagon" system. b) If the child in the wagon has a mass of 40 kg and the wagon has a mass of 9 kg, what is the acceleration of the child in the wagon?

Problem 3: Two children push horizontally on a third child who is sitting fixed in a wagon that has essentially frictionless wheels. The first child pushes in the positive x-direction with a force of magnitude 70 N while the second child pushes in the negative x-direction with a force of magnitude 95 N. a) Draw a free-body diagram of the "child-in-the-wagon" system. b) If the child in the wagon has a mass of 40 kg and the wagon has a mass of 9 kg, what is the acceleration of the child in the wagon?

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter4: Dynamics: Force And Newton's Laws Of Motion

Section: Chapter Questions

Problem 9PE: Suppose two children push horizontally, but in exactly opposite directions, on a third child in a...

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Suppose two children push horizontally, but in exactly opposite directions, on a third child in a wagon. The first child exerts a force of 75.0 N, the second a force of 90.0 N, friction is 12.0 N, and the mass of the third child plus wagon is 23.0 kg. (a) What is the system of interest if the acceleration of the child in the wagon is to be calculated? (b) Draw a free-body diagram, including all forces acting on the system. (c) Calculate the acceleration. (d) What would the acceleration be if friction were 15.0 N?
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Two children, Raffi and John, sitting on sleds tied together with a massless rope, are being dragged across a frozen river by their playful Siberian husky Rex who is supplying a 112-N horizontal force (Fig. P5.78). The coefficient of friction between the sleds and the ice is 0.08, the combined mass of Raffi and his sled is 42.0 kg, and the combined mass of John and his sled is 51.0 kg. a. Draw a free-body diagram for each of the childsled systems. b. What is the acceleration of the system? c. What is the tension FT in the rope connecting the two sleds? FIGURE P5.78