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The simple pendulum. θ. L. m. The simple pendulum. θ. L. m. mg. The simple pendulum. θ. L. m. mg sin θ. mg. The simple pendulum. θ. L. x. m. mg sin θ. mg. Some trig: sin θ = x L
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The simple pendulum θ L m
The simple pendulum θ L m mg
The simple pendulum θ L m mg sinθ mg
The simple pendulum θ L x m mg sinθ mg
Some trig: sin θ = x L For small angles ( < 5 0) θ = x in radians L θ L x m mg sinθ mg
Some trig: sin θ = x L For small angles ( < 5 0) θ = x in radians L θ L + x m mg sinθ mg
Some trig: sin θ = x L For small angles ( < 5 0) θ = x in radians L θ L Restoring force = - mg sinθ + x m mg sinθ mg
Some trig: sin θ = x L For small angles ( < 5 0) θ = x in radians L θ L Restoring force = - mg sinθ ( -ve sign indicates a left displacement and a right restoring force) + x m mg sinθ mg
Some trig: sin θ = x L For small angles ( < 5 0) θ = x in radians L θ L Restoring force = - mg sinθ ( -ve sign indicates a left displacement and a right restoring force) Restoring force = - mg x L + x m mg sinθ mg
Some trig: sin θ = x L For small angles ( < 5 0) θ = x in radians L θ L Restoring force = - mg sinθ ( -ve sign indicates a left displacement and a right restoring force) Restoring force = - mg x L From Newton’s second law F=ma + x m mg sinθ mg
Some trig: sin θ = x L For small angles ( < 5 0) θ = x in radians L θ L Restoring force = - mg sinθ ( -ve sign indicates a left displacement and a right restoring force) Restoring force = - mg x L From Newton’s second law F=ma ma = - mg x L + x m mg sinθ mg
Some trig: sin θ = x L For small angles ( < 5 0) θ = x in radians L θ L Restoring force = - mg sinθ ( -ve sign indicates a left displacement and a right restoring force) Restoring force = - mg x L From Newton’s second law F=ma ma = - mg x L + x m mg sinθ mg
Some trig: sin θ = x L For small angles ( < 5 0) θ = x in radians L θ L Restoring force = - mg sinθ ( -ve sign indicates a left displacement and a right restoring force) Restoring force = - mg x L From Newton’s second law F=ma and a = - g x L + x m mg sinθ mg
Some trig: sin θ = x L For small angles ( < 5 0) θ = x in radians L θ L Restoring force = - mg sinθ ( -ve sign indicates a left displacement and a right restoring force) Restoring force = - mg x L From Newton’s second law F=ma and a = - g x L Compare with SHM equation: a = - (2πf)2 x + x m mg sinθ mg
and a = - g x L Compare with SHM equation: a = - (2πf)2 x θ L + x m mg sinθ mg
and a = - g x L Compare with SHM equation: a = - (2πf)2 x - (2πf)2 = - g L θ L + x m mg sinθ mg
and a = - g x L Compare with SHM equation: a = - (2πf)2 x - (2πf)2 = - g L f = 1 g 2π L θ L + x m mg sinθ mg
and a = - g x L Compare with SHM equation: a = - (2πf)2 x - (2πf)2 = - g L f = 1 g 2π L T = 2π L g θ L + x m mg sinθ mg
and a = - g x L Compare with SHM equation: a = - (2πf)2 x - (2πf)2 = - g L f = 1 g 2π L T = 2π L g θ L + x Discuss: effect of length, mass, gravity, angle of swing. m mg sinθ mg
T = 2πL g
T = 2πL g Put in the form: y = m x + c
T = 2πL g Put in the form: y = m x + c T 2 = 4 π 2L + 0 g
T = 2πL g T 2 /s 2 Put in the form: y = m x + c T 2 = 4 π 2L + 0 g L / m
T = 2πL g T 2 /s 2 Put in the form: y = m x + c T 2 = 4 π 2L + 0 g L / m Ts Max force on pendulum bob occurs as it passes through the equilibrium: m mg
T = 2πL g T 2 /s 2 Put in the form: y = m x + c T 2 = 4 π 2L + 0 g L / m Ts Max force on pendulum bob occurs as it passes through the equilibrium: m mv2 = Ts - mg r mg
T = 2πL g T 2 /s 2 Put in the form: y = m x + c T 2 = 4 π 2L + 0 g L / m Ts Max force on pendulum bob occurs as it passes through the equilibrium: m mv2 = Ts - mg but r = L so mv2 = Ts - mg r L mg