General Physics 1 PDF
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Uploaded by ProfoundSurrealism
Mount Carmel School of Infanta
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These notes cover topics on work, power, and energy in general physics, including examples and solved exercises. Concepts such as kinetic and potential energy are included. This appears to be a set of class notes for a secondary school physics class held at Mount Carmel School of Infanta.
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Lesson I: Units and Measurement GENERAL PHYSICS 1 WORK, POWER AND ENERGY WORK is the product of force and displacement resulting from the application of force. The unit of Work is Joule ( π± ). πΎπ = π π π πΎπ = ππ ππππ½ π = Force applied (in Newtons) π = D...
Lesson I: Units and Measurement GENERAL PHYSICS 1 WORK, POWER AND ENERGY WORK is the product of force and displacement resulting from the application of force. The unit of Work is Joule ( π± ). πΎπ = π π π πΎπ = ππ ππππ½ π = Force applied (in Newtons) π = Displacement (in meters) ΞΈ = Angle between force and displacement Example: 1 A crate is moved 2m along a horizontal floor at a constant speed by a force of 50N. How much work is done on the crate by the force. Given: πΉ = 50 π π =2π π πππ’ππππ π‘π ππππ: ππ ππ = πΉ π₯ π = 50 2 = 100π½ Example: 2 A crate is moved 2m along a horizontal floor at a constant speed by a force of 50N which makes an angle of 30 degree above the horizontal. How much work is done on the crate by the force. Given: πΉ = 50 π π =2π π = 30 π πππ’ππππ π‘π ππππ: ππ ππ = πΉπππ ππ = 50(2) cos 30 = 86.6π½ Example: 3 A mechanic pushes a 1000 kg car along a flat road over the distance of 20 meters. How much work does the mechanic do on the car? Given: π = 1000ππ π = 20 π πππ‘π: πΉ = ππ POWER is the speed or rate of work. The unit of Power is watts ( πΎ ). πΎπ π·= π πΎπ = Work (in joule) t = Time (in second) Example: How long will it take a 25000W motor to lift 90kg block 35m high Given: π = 25000π π = 90 ππ π = 35 π π‘ =? ENERGY ability to a work. Types of Energy Kinetic Energy - Energy of an object due to its motion. Potential Energy - Energy stored due to an objectβs position or state. Kinetic Energy - Energy of an object due to its motion. π π²π¬ = πππ π π = Mass (in kilograms) π = Velocity (in meters per second) Example: A 3kg block slides on a frictionless surface at 20m/s. How much kinetic energy does it have? Given: π = 3ππ π£ = 20 π/π π π²π¬ = π(ππ)π = ππππ± π Potential Energy - Energy stored due to an objectβs position or state. Gravitational Potential Energy: where: π·π¬ = πππ π = Mass (in kilograms) π= Acceleration due to gravity (9.8 m/sΒ²) π= Height (in meters) Example: Find the potential energy of a 57kg student that goes up on the stairway with height of 7.98 meters? Given: π = 57ππ π£ = 7.98π π·π¬ = πππ = ππ π. ππ π. ππ = ππππ. ππ π± Activity 2 1. A 25kg crate is lifted from 230m above the ground in 350 seconds. a. How much work is required to lift it into the air b. What is the average power exerted on the crate. 2. A 7.5kg rock moving in space has 438J of kinetic Energy. How fast is it moving? 3. Using a rope, a fireman climb the building vertically up to a distance of 9 meters. If his potential energy is at that point is 3950 joules, what is the weight of the fireman? MCSI-SHS Thank You ! Enjoy the rest of the day! - Sir Allen
