You've experienced convection cooling if you've ever extended your hand out the window of a moving vehicle or into a flowing water stream. with the surface of your hand at a temperature of 30 degree c. determine the convection heat flux for a vehicle speed of 35 km/h in air at -5 degree c with a convection coefficient of 40 w/m2 . k and a velocity of 0.2 m/s in a water stream at 10 degree c with a convection coefficient of 900 w/m2 k. which condition would feel colder? contrast these results with a heat loss of approximately 30 w/m2 under normal room conditions.

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 790 n/m. it is initially at rest on an inclined plane that is at an angle of 28 degrees with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is k = 0.14. in the initial position, where the spring is compressed by a distance of a = 0.18 m, the mass is at its lowest position and the spring is compressed the maximum amount. take the initial gravitational energy of the block as zero. b) if the spring pushes the block up the incline, what distance, l, in meters will the block travel before coming to rest? the spring remains attached to both the block and the fixed wall throughout its motion.

Aregion of space in which a measurable gravitational force is indicated by the force exerted on a test mass is called

In a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina. what should be the radius of curvature of the cornea such that the image of an object 40.0 cm from the cornea’s vertex is focused on the retina?