1.A body of certain mass is kept at a height of 15m from the ground, taking the value of g as 10m/s find out the mass of the body when it posses the energy of 300J. 2. A boy runs at a velocity of 50m/s. If he has the mass of 50kg what will be the energy possessed by him?

Iwill give 30 points to whoever answers ! what is the formula for actual mechanical advantage and ideal mechanical advantage?

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.

The radius of an atom is closest in size to a