9. If in a gymnasium a pupil takes 3 sec. to swing once across while hanging from a ring, how long a pendulum is formed?

10. A clock pendulum makes four vibrations a second, what is its length?

Review Outline: Force and Motion

Force; definition, elements, how measured, units, dyne.

Graphic Representation; typical examples of finding a component, a resultant, or an equilibrant.

Motion; Laws of motion (3), inertia, curvilinear motion, centrifugal force, momentum, (M = mv), reaction, stress and strain.

Moment of Force; parallel forces, couple, effective and non-effective component.

Gravitation; law; gravity, center of; weight. Equilibrium 3 forms; stability, how increased.

Falling Bodies; velocity, acceleration, "g," Laws; V = gt, S = (1/2)gt2 - s = (1/2)g(2t - 1).