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Physics. the scientific study of matter, energy, force, and motion, and the way they relate to each other. Kinematics. study of motion: a branch of physics that deals with the motion of a body or system without reference to force and mass. Scalar or Vector?.
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Physics the scientific study of matter, energy, force, and motion, and the way they relate to each other.
Kinematics study of motion:a branch of physics that deals with the motion of a body or system without reference to force and mass
Scalar or Vector? Scalar: quantity with magnitude but not direction ex. 30oC is a scalar quantity Vector: quantity with direction and magnitude. ex. 40.0N upwards is a vector quantity
Scalar or Vector? Temperature Scalar Time Scalar AccelerationVector Energy Scalar Force Vector
Position location:the place where somebody or something is, especially in relation to other things When describing location, include magnitude, location, & point of origin ex. 25m left of the elevator
Distance length between two things:the length of the space separating two people, places, or things 25m
If you walk 1.5km north, then 2.0km south, then 4.0km north, what is the distance travelled? 1.5km + 2.0km + 4.0 km =7.5km
Displacement amount of movement in particular direction:the amount of movement of an object measured in a particular direction 25m to the left 25m east
If you walk 1.5km north, then 2.0km south, then 4.0km north, what is your displacement? 1.5km + (-2.0km) + 4.0 km =3.5km
Pop Quiz • Which is the vector quantity? • $100.00 • 54o north • 20 kg • 60 km/h It is 54o north. It has magnitude and direction.
Calculate the displacement: With a false start, a racer begins a 100.0m dash 2.0m ahead of the starting line. What is her displacement when she finishes? ∆d = df- di 100.0m - 2.0m = 98.0m 98.0m past the starting line.
A person travels 12m to the left and then 8m to the left. • What is the distance travelled? • What is the displacement? a) 12m + 8m = 20m Direction should not be given because distance is not a vector. b) 12m + 8m = 20m to the left
A person travels 12m to the left and then 8m to the right. • What is the distance travelled? • What is the displacement? a) 12m + 8m = 20m Direction should not be given because distance is not a vector. b) 12m + (-8m) = 4m The direction is to the left because the difference is positive.
Speed: the amount distance changes over time. • Speed = Distance • Time • Velocity is speed that has direction. • Velocity = Displacement • Time • Therefore, a person walking eastward has a different velocity than a person walking at the same speed westward.
Units for Velocity? Kilometers per hour Metres per second Converting m/s to km/h 100 km/h 100000 m/h 1670 m/min 27.8 m/s 3.6 km/h 3600 m/h 60 m/min 1 m/s