Asmall pebble is heated and placed in a foam cup calorimeter containing 25.0 ml of water at 23.0°c. the water reaches a maximum temperature of 24.2°c. how many joules of heat were released by the pebble? (the specific heat capacity of water is 4.18 j/g•°c and the density of water is 1.00 g/ml)

Aphysical change is a change in the size, shape,, or stafe of matter true or false

Asheet of steel 1.5 mm thick has nitrogen atmospheres on both sides at 1200oc and is permitted to achieve a steady-state diffusion condition. the diffusion coefficient for nitrogen in steel at this temperature is 6 x 10- 11 m2 /s, and the diffusion flux is found to be 1.2 x 10-7 kg/m2 -s. also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 4 kg/m3 . how far into the sheet from this high-pressure side will the concentration be 2.0 kg/m3 ? assume a linear concentration profile.

If a simple machine reduces the strength of a force, what must be increased?