How far should pencil held from a convex mirror of radius 80 cm to form an image one-half the size of the pencil?

Asmall grinding wheel has a moment of inertia of 4.0×10−5 kg⋅m2 . what net torque must be applied to the wheel for its angular acceleration to be 150 rad/s2 ?

Ahypothetical metal has an orthorhombic unit cell for which the a, b, and c lattice parameters are 0.413 nm, 0.665 nm, and 0.876 nm, respectively. (a) if there are 8 atoms per unit cell and the atomic packing factor is 0.536, determine the atomic radius (in nm). (b) if the density is 3.99 g/cm3, calculate the metal's atomic weight (in g/mol).

Pressure is a measure of force per unit area or p=f/ap=f/a. a student is checking the amount of pressure their car exerts upon the road. the car weighs 22 tons ( us short ton ). the student finds the dimensions of each tire's footprint on the road is 12.5 cm x 16.5 cm. in pounds per square inch (psi), what is the total pressure the car exerts upon the road?