Question

5) (10 pts) John is baby-sitting Casey, his 3-year old brother. He puts a crash helmet on Casey, places him in the red wagon and takes him on a stroll through the neighborhood. As John starts across the street, he exerts a 58 N forward force on the wagon. There is a 20 N resistance force (friction) and the wagon and Casey have a combined weight of 302 N. Construct a free body diagram showing all the forces acting upon the wagon. Determine the net force, mass and acceleration of the wagon. 6) 10 pts) Jack and Jill are members of the stage crew for the Variety Show. Between acts, they must quickly move a Grand Piano onto stage. After the curtain closes, they exert a sudden forward force of 534 N to budge the piano from rest and get it up to speed. The 158-kg piano experiences 318 N of friction a) What is the piano's acceleration during this phase of its motion? b) If they maintain this forward force for 1.4 seconds, then what speed will the piano have? 7) (10 pts) A rope is used to pull a 2.9-kg bucket of water out of a deep well a) What is the acceleration of the bucket when the tension in the rope is 33 N? b) If starting from rest, what speed will the bucket have after experiencing this force for 2.6 seconds? 8) (10 pts) A 1300-kg car is skidding to a stop along a horizontal surface. The car decelerates from 27 m/s to a rest position in 4.5 seconds. Assuming negligible air resistance, a) determine the friction between the car tires and the road surface. b) determine the coefficient of kinetic friction 9. (10 points) The displacement vector from the grocery store door to your car is Ax (5 i - 8 j )m But because of the strong gust, you have to apply a force F in a slightly different direction to keep your cart moving straight from the door to the car (30 i5T j ) N F How much work do you do? 10. 10 pts.) Barbara is pulling on a rope to drag her backpack to school across the ice. She pulls upwards and rightwards with a force of 29 N at an angle of 35 degrees above the horizontal to drag the backpacka horizontal distance of 129 m to the right. What's the work done upon the backpack?

Answer 1

}Please, post other questions separately

at the net force the net F=F-fo Fx = 58-20=320 for VW the mass M-W - 301 - 3008 kg the acceleration a=Fx = 1.04M sz