Equation h(t) = -5+ ²+ 30t gives the height
in meters above the ground after t second's of a throw rock.
The rock is thrown from a window of a building
that is
O meters above the ground. The upwand
velocity of the rock is 30 sec. Complete the table of
values and a graph of the entire vertical flight of the rock,
b
Given h(t) at tltta the time to reach the maximum height an
he) -5300
times
2a
b

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.