A100 kg box on the right and a 50 kg box on the left are tied together by a horizontal cable. the 100 kg box is acted upon by an external force of 500 n to the right. the frictional force exerted by the floor on the 100 kg box is 30 n and the frictional force exerted by the floor on the 50 kg box is 20 n. in this problem, orient your axex such that the right direcion is positive and the left direction is negative. what is the net force on the 100 kg block.
is the answer zero?

The two most prominent wavelengths in the light emitted by a hydrogen discharge lamp are 656 nm(red) and 486 nm (blue). light from a hydrogen lamp illuminates a diffraction grating with 520lines/mm , and the light is observed on a screen 1.5m behind the grating. part a what is the distance between the first-order red and blue fringes? express your answer to two significant figures and include the appropriate units.

Asteam power plant operates on an ideal reheat rankine cycle between the pressure limits of 15 mpa and 10 kpa. the mass flow rate of steam through the cycle is 12 kg/s. steam enters both stages of the turbine at 500°c. if the moisture content of the steam at the exit of the low-pressure turbine is not to exceed 10 percent, determine (a) the pressure at which reheating takes place, (b) the total rate of heat input in the boiler, and (c) the thermal efficiency of the cycle. also, show the cycle on a t-s diagram with respect to the saturation lines. (2.15 mpa; 45.0 mw; 42.6%)

If steel is more dense that lake water, why can a boat float