Pulverized coal particles at 300 K are injected into hot furnace gases at 1500 K. Estimate the initial heating rate of a 70μm-diameter particle. Express your result in kelvins per second. TXhe convective heat-transfer coefficient is approximately 1500 W/m²· K.

The specific heat and density of the coal are 1.3 kJ/kg · K and 1650 kg/m³, respectively.