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[Virtual Presenter] Shams Mohammed Mahdi Force (Grade 7 c).
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[Virtual Presenter] What is a force? A force is a push or pull that causes an object to move, stop, or change direction In physics a force is anything that makes an object accelerate If an object is stationary, it won’t start moving without a force.
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[Virtual Presenter] A force cannot be seen and described like an object but its effect on different object can be seen so we can define it as: Force is an effect which can : Start motion Stop motion Change speed or direction of motion Change shape or size of body.
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[Audio] Action and motion Force Measurement and Units SI unit for force is the Newton A Newton is a force that causes a 1 kilograms mass to accelerate at a rate of 1m/s/s. 1 N (Newton) = 1 kilograms * m/s/s We use a spring scale to measure force. Force always occur in pairs acting in opposite directions. For every action force. There is always an equal but opposite reaction force.
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[Audio] Type of force Stronge force Electromagnetic force Weak force Gravitational force Fractional force a resistive force that acts between two surfaces in contact, opposing their relative motion or tendency to move.
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[Audio] Forces in the Same Direction Combining Forces When forces are applied in the same direction, they are added to determine the size of the net force..
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[Audio] Combining Forces at Right Angles Forces in Different Directions When two forces act in opposite directions, you subtract the smaller force from the larger force to determine the net force. The net force will be in the same direction as the larger force. Use the Pythagorean Theorem. a2 plus b2 = c2. Can only use if adding only 2 vectors that make a right angle. C A B.
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[Audio] Balanced Forces Balanced and Unbalanced Forces Forces occur in pairs and they can be either balanced or unbalanced Balanced forces do not cause a change in motion They are equal in size and opposite in direction The net force is 0.
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[Audio] “Unbalanced” Forces If one side of the scale has more mass, then gravity will accelerate it down! If the multiple forces acting at one time are not balanced out (equal), then acceleration can/will occur on the object! Kicking the ball causes it to move quickly in a different direction.
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[Audio] An unbalanced force always causes a change in motion The net force is greater than 0 When unbalanced forces act in opposite directions you can find the net force Net force Magnitude The difference between the two forces Direction Direction of the largest force.
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[image]. SECRES FORc?.