A steam engine intakes 50 g of steam at 100$$^\circ$$C per minute and cools it down to 20$$^\circ$$C. If latent heat of vaporization of steam is 540 cal g$$-$$1, then the heat rejected by the steam engine per minute is __________ $$\times$$ 103 cal.
(Given : specific heat capacity of water : 1 cal g$$-$$1 $$^\circ$$C$$-$$1)
The first overtone frequency of an open organ pipe is equal to the fundamental frequency of a closed organ pipe. If the length of the closed organ pipe is 20 cm. The length of the open organ pipe is _____________ cm.
The equivalent capacitance between points A and B in below shown figure will be __________ $$\mu$$F.
A resistor develops 300 J of thermal energy in 15 s, when a current of 2 A is passed through it. If the current increases to 3 A, the energy developed in 10 s is ____________ J.