Suppose the ends of the rail are rigidly clamped at 0°C to prevent expansion.
Calculate the thermal stress in the rail if
its temperature is raised to 34°C. Young's
modulus for steel is 20 x 1010 N/m².
Answer in units of N/m².

Red light strikes a metal surface and electrons are ejected. if violet light is now used with a 10% greater intensity, what will happen to the ejection rate (number of ejected electrons per second) and the maximum energy of the electrons? a) greater ejection rate; same maximum energyb) same ejection rate; greater maximum energyc) greater ejection rate; greater maximum energyd) same ejection rate; same maximum energye) none of the above answers are correct

Arocket starts from rest and moves upward from the surface of the earth. for the first 10.0 s of its motion, the vertical acceleration of the rocket is given by ay = 12.80 m/s32t, where the +y-direction is upward. (a) what is the height of the rocket above the surface of the earth at t = 10.0 s? b) what is the speed of the rocket when it is 325 m above the surface of the earth?

Abowling ball rolling down the lane toward the pins has gravitational potential energy. a. no b. a lot of c. a little