Person is lifting a 250 n dumbbell. the weight is 30 cm from the pivot point of the elbow. what force must be exerted five from the elbow to lift the weight? assume everything is perpendicular.

True or false when elements combine to form a mixture, the resulting chemical properties may be very different from those of the elements that make it.

Where is the potential energy throughout the loading, cocking, and releasing of the trebuchet?

The period of a pendulum varies directly as the square root of the length of the pendulum and inversely as the square root of the acceleration due to gravity. find the period when the length is 144 cm and the acceleration due to gravity is 980 cm per second squared, if the period is 7pi seconds when the length is 289 cm and the acceleration due to gravity is 980 cm per second squared.