- #1
Kinermatics
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Homework Statement
1. A truck is pulling a car on a horizontal highway using a horizontal rope. The car is in neutral gear, so we can assume that there is no appreciable friction between its tires and the highway. As the truck is accelerating to highway speeds, draw a free-body diagram of the truck. (Assume that the truck is accelerating to the right.)
2. A large box containing your new computer sits on the bed of your pickup truck. You are stopped at a red light. The light turns green and you stomp on the gas and the truck accelerates. To your horror, the box starts to slide toward the back of the truck. (Assume that the truck is accelerating to the right.) Draw clearly labeled free-body diagram for the truck. (The bed of the truck is not frictionless.)
Homework Equations
Just drawing
The Attempt at a Solution
1. I know i have the weight and the normal force correct (weight pointing down and normal force pointing opposite) however I can't seem to figure out where to put: the Tension force and the Friction force. My first instinct was to put the friction force left (isn't the direction of friction opposite that of motion) and to put the Tension force left (the tension is always pointing towards the rope). Idk somewhere i did something wrong.
2. This part is very confusing. Like the previous problem i know i got the weight and normal force part correct. But for this question they want to know the direction and orientation of: 1. the box's friction force on the truck bed 2. reaction force to tires' backward push 3. reaction to the normal force on the box from the truck.
Here are better illustrations of my attempt:
1.http://img685.imageshack.us/img685/7545/95398466.jpg
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2.http://img804.imageshack.us/img804/7533/51523982.jpg
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