The picture shows an arm lifting a barbell. The total mass of the barbell is 2.5 kg. The distance between the man's elbow and hand is 46 cm. The distance between the man's elbow and shoulder is 45 cm. The angle between his forearm and the horizontal (labeled "1") is 38 degrees. The angle between his upper arm and the horizontal (labeled "2") is 19 degrees. Calculate the torque exerted by the barbell's weight about his elbow.

Suppose that f : rn → rm and that a ∈ k, where k is a connected subset of rn . suppose further that for each x ∈ k there exists a δx > 0 such that f(x) = f(y) for all y ∈ bδx (x). prove that f is constant on k; that is, f(x) = f(a) for all x ∈ k

Assume that two of the electrons at the negative terminal have attached themselves to a nearby neutral atom. there is now a negative ion with a charge -2e at this terminal. what are the electric potential and electric potential energy of the negative ion relative to the electron? the electric potential and the electric potential energy are both twice as much. the electric potential is twice as much and the electric potential energy is the same. the electric potential is the same and the electric potential energy is twice as much. the electric potential and the electric potential energy are both the same. the electric potential is the same and the electric potential energy is increased by the mass ratio of the oxygen ion to the electron. the electric potential is twice as much and the electric potential energy is increased by the mass ratio of the oxygen ion to the electron.

Diverging mirrors and lenses always produce images