Agenda1. Warm Up2. Check HW3. Notes: Torque4. C#11

Warm UpA vertical spring with a spring constant of 5Nm, has a 1 kg mass hanging from it. It undergoes simple harmonic motion. if the amplitude of the wave motion is 1 meter, what is the maximum distance the string can be stretched? What is the energy at this point?

HomeworkEquations Quiz Friday: Centripetal Motion, Gravitation, Torque, & Simple Harmonic Motion

Torque,CircularMotion,Gravitation,&Simple Harmonic Motion Test Monday

AP PhysicsTuesday 14.02.17Standards: 2a1 Calculate the magnitude and direction of the torque associated with a given force.

Objective: SWBAT solve problems involving Torque

AP PhysicsWednesday 14.02.18 Standards: 2a1 Calculate the magnitude and direction of the torque associated with a given force.

Objective: SWBAT analyze situations by using rotational and translational equilibrium.

Agenda1. Warm Up2. Torque Notes3. Torque Guided Practice

HomeworkC#11 Torque

Warm UpFind the maximum speed of a pendulum if the length of the pendulum is 2 m, the pendulum swings at an angle of 15 degree to the vertical, and a 4 kg mass is hanging from the pendulum.

AP PhysicsThursday 14.02.19Standards:

Standards: 2a1 Calculate the magnitude and direction of the torque associated with a given force.

Objective: SWBAT solve problems involving Torque

HomeworkC#12

Warm UpFind the torque caused by a 20 N force acting at an angle of 45 degrees to a 10 m rod.

Agenda1. Warm up. Answer 141 Nm2. Pass out C#123. Work on Worsheet C#11&C#12

AP PhysicsFriday 14.02.20Standards: Standards: 2a1 Calculate the magnitude and direction of the torque associated with a given force.

Objective: SWBAT solve problems involving Torque & Equilibrium.

HomeworkC#13

Warm UpA 20 m long uniform 10 kg bar hangs from a rope 8 meters from one end as shown below. Fill in the diagram with the givens. How much mass would need to be placed on the edge of the bar for it to balance.

Agenda1. Warm Up2. Review HW3. Torque Questions?4. Free Response Torque Practice C#13

C#11 Torque

1. (1) The nests built by the mallee fowl of Australia can have masses as large as 3.00x105kg. Suppose a nest with this mass is being lifted by a crane. The boom of the crane makes an angle of 45.0° with the ground. If the axis of rotation is the lower end of the boom at point A, the torque produced by the nest has a magnitude of 3.20x107Nm. Treat the boom’s mass as negligible, and calculate the length of the boom.

2. (3) A meterstick of negligible mass is fixed horizontally at its 100.0 cm mark. Imagine this meterstick used as a display for some fruits and vegetables with record-breaking masses. A lemon with a mass of 3.9 kg hangs from the 70.0 cm mark, and a cucumber with a mass of 9.1 kg hangs from the x cm mark. What is the value of x if the net torque acting on the meterstick is 56.0 Nm in the counterclockwise direction?

A. F=100 N r=50m

τ=?

B. F=20 N r=20m θ=30°

τ=?

C.F=10Nr=4Nθ=40°

rF

θ

D.F=10Nr=4NΦ=40°

r

FΦ

C#12 Torque& EquilibriumSorry about yesterday’s guided practice, it was way too complicated for an intro. I did not select it carefully enough. Do your best. Notes are on the board.

A.F=6Nr=8Nθ=20°

F

θr

mrodg

FapB.Fap=20Nl=10m r=0.5mTnet=? m=5kg

l

r

1. A uniform meterstick of mass 0.20 kg is pivoted at the 40 cm mark. Where should one hang a mass of 0.50 kg to balance a stick? -- 36 cm

2. A meterstick of negligible mass is placed on a fulcrum at the 0.60 m mark, with a 2.0 kg mass hung at the 0m position. Immediately after release, the magnitude ofthe net torque on the meterstick about the fulcrum is most exactly? 8.0 Nm

3. A meterstick is supported at each side by a spring scale. A heavy mass is then hung on the meterstick so that the spring scale on the left hand side reads four times the value of the spring scale on the right hand side. If the mass of the meterstick is negligible compared to the hanging mass, how far from the right hand side is the large mass hanging. 80 cm