Mary and her sister are playing with a cardboard box on the neighborhood hill. Mary climbs into the box, the total mass of the box with Mary in it is 115 kg. The box starts at rest at the beginning of the incline. The hill is at an incline of 28 degrees with respect to the horizontal.The static and kinectic friction between the box and hill is 0.4 and 0.2 respectively. Assume that Mary is now in the box, but has not started to move. a. What is the gravitational force acting on the box and child system? b. What is the magnitude of the normal force acting on the box? c. What is the reaction force associated with the normal force found in the previous step

Mary and her sister are playing with a cardboard box on the neighborhood hill. Mary climbs into the box, the total mass of the box with Mary in it is 115 kg. The box starts at rest at the beginning of the incline. The hill is at an incline of 28 degrees with respect to the horizontal.The static and kinectic friction between the box and hill is 0.4 and 0.2 respectively. Assume that Mary is now in the box, but has not started to move. a. What is the gravitational force acting on the box and child system? b. What is the magnitude of the normal force acting on the box? c. What is the reaction force associated with the normal force found in the previous step

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.35P: The weight of the cylindrical tank is negligible in comparison to the weight of water it contains...

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Mary and her sister are playing with a cardboard box on the neighborhood hill. Mary climbs into the box, the total mass of the box with Mary in it is 115 kg. The box starts at rest at the beginning of the incline. The hill is at an incline of 28 degrees with respect to the horizontal.The static and kinectic friction between the box and hill is 0.4 and 0.2 respectively. Assume the box is sliding downhill. a. What is the magnitude of the acceleration of the box? (same as Problem 3b)b. If the hill is 5m tall, what is the Mary's speed when she reaches the bottom?c. At the bottom of the hill, the ground becomes level, but the coefficients offriction do not change. How far will Mary slide before she comes to a stop?
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