A1.40 kg block is attached to a spring with spring constant 15.5 n/m . while the block is sitting at rest, a student hits it with a hammer and almost instantaneously gives it a speed of 43.0 cm/s . what are the block's speed at the point where x= 0.650 a

Consider a 1000 w iron whose base plate is made of 0.5 cm thick aluminum alloy 2024-t6 (ρ = 2770 kg/m3 and cp = 875 j/kg°c). the base plate has a surface area of 0.03 m2. initially, the iron is in thermal equilibrium with the ambient air at 22°c. assuming 90% of the heat generated in the resistance wires is transferred to the plate, determine the minimum time needed for the plate temperature to reach 200°c.