Scalars - magnitude only (eg: mass, time, energy, speed)
Vectors - magnitude and direction (eg: displacement, force, velocity, momentum, acceleration)
ADDING VECTORS- Draw vectors tip to tail and form a triangle. Use pythagoras and SOHCAHTOA to find resultant force and direction (angle). Remember ~ look out for which angle they give you, it depends on whether you use sin or cos for 2D motion.
SUVAT- Motion with UNIFORM acceleration. S- Displacement (m) U- Initial Velocity (ms^-1) V -Final velocity(ms^-1) A- Acceleration (ms^-2) T- Time (s)
3 most common used ~ v^2 = u^2 + 2as, v = u +at, and s= ut + 1/2 a t^2 (for freefall, a = g = 9.81)
Freefall = all objects feel a force due to Earth's gravitational field that depends on their mass (f = ma ~ which is related to Newton's Second Law)
Remember for exam, falling trap door experiment with a steel ball and an electro-magnet connected to a timer. Repeat exp. a few times with various heights. You find g using a graph height against time taken (squared)- gradient would equal 1/2 g.
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