# A strap inclined upward at a 45 angle pulls a

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Question:A strap inclined upward at a 45° angle pulls a suitcase through the airport. The tension in the strap is 20 N. How much work does the tension do if the suitcase is pulled 100 m ?  Unlike momentum or energy, work is not what an object has! Work is something that an object does A point to remember
Mechanical EnergyMechanical energy is due to position or due to motion, or both.There are two forms of mechanical energy:Potential energyKinetic energy
Potential EnergyStored energy held in readiness with a potential for doing workExamples: A stretched bow has stored energy that can do work on an arrowA stretched rubber band of a slingshot has stored energy and is capable of doing work
Gravitational potential energyEqual to the work done (force required to move it upward the vertical distance moved against gravity) in lifting itIn mathematical form it can be represented as: Potential energy = mass x acceleration due to gravity x height
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Question:Ball A has half the mass and eight times the kinetic energy of ball B. What is the speed ratio vA/vB?
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