Ablackened, solid copper sphere of radius 4.00 cm hangs in a vacuum in an enclosure whose walls have a temperature of 20.0°c. if the sphere is initially at 0°c, find the rate at which its temperature changes, assuming that heat is transferred by radiation.

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 710 n/m. it is initially at rest on an inclined plane that is at an angle of θ = 23° with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is μk = 0.19. in the initial position, where the spring is compressed by a distance of d = 0.16 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. a) what is the block's initial mechanical energy? 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.

Time remainin52: 42the chart shows data for a moving object. which conclusion is best supported by the information inthe chart? time (s)velocity (m/s

What is the primary force that suspension bridges use cables to hold their spans up? a. tension force b. resistance force c. normal force d. elastic force e. applied force