A hot plane surface at 100°C is exposed to air at 25°C with a combined heat transfer coefficient of 20W/m2*K The heat loss from the surface is to be reduced by half by covering it with sufficient insulation with a thermal conductivity of 0.1 W/m*K. Assuming the heat transfer coefficient to remain constant, the required thickness of insulation is

(a) 0.1cm
(b) 0.5 cm
(c) 1.0 cm
(d) 2.0 cm
(e) 5 cm

Calculate the heat capacity per object when the total energy is 4 quanta. (think of this in terms of increasing from 3.5 quanta of energy in the system to 4.5 quanta of energy in the system, if that were possible.) c4 = __ j/k/object

Which statement correctly describes the current in a circuit that is made up of any two resistors connected in parallel with a battery? a. the current in the battery and in each resistor is the same b. the current the battery equals to the sum of the currents in the resistors c.the current in the battery is less than the current in either resistor d. the current in the battery equals to the product of the currents in the resistors

There are two-speed cameras, one in an are where the speed limit is 30 km/h and another where the speed limit is 50 km/h. in which will there be a smaller time interval between the photographs? explain your answer.