A decorative plastic film on a copper sphere of 10 mm diameter in an oven at 750C. Upon removal from the oven, the sphere is subjected to an air stream at 1 atm. , and 230C having a velocity of 10 meter/sec. Estimate how long it will take to coal the sphere to 350C? Density of copper is 8933 kg/m3 , thermal conductivity k = 399 W/m. K and specific heat Cp = 387 J/kg. K. for Air at an average temperature of T[infinity] = 296 K has viscosity µ= 181x10-7 N. s/m2 , kinematic viscosity ν = 15.36x10-6 m2/s and thermal conductivity k = 0.0258 W/m. K and Prandtl No. Pr = 0.709 and air at surface temperature Ts = 328 K will have viscosity µs = 197x10-7 N. s/m2

here we know that ball will drop down by total distance 3.2 m

so here we know that

now using kinematics

now in the same time it will cover horizontal distance of 0.75 m

so speed of the ball will be

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

im srry but ur wrong the answer is d a smooth rock, some red dirt, and an empty bird's nest.