A 1200 kg bus moving at 20 m/s takes a turn around a circle with a radius of 20 m. Determine the net force acting upon the bus.

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.

What kind of simple machine is a catapult?

A90db sound wave strikes an eardrum whose area is 5.0×10^-5m^2. how much energy is absorbed by the eardrum per second