Why is the standard model unable to predict a particle's mass?
A. It is not precise enough to predict mass.
B. It lacks a mathematical model to predict mass.
C. It can observe only first-generation leptons.
D. It can observe only first-generation quarks.

Arod of some material 0.20 m long elongates 0.20 mm on heating from 21 to 120°c. determine the value of the linear coefficient of thermal expansion [in (degrees c)^-1] for this material.

Suppose a wheel with a tire mounted on it is rotating at the constant rate of 2.15 times a second. a tack is stuck in the tire at a distance of 0.373 m from the rotation axis. noting that for every rotation the tack travels one circumference (a) find the tack's tangential speed. (b) what is the tacks radial acceleration?

Sound is a disturbance that travels through a medium as a