Answer questions 12-20
An electric clothes dryer is rated at 5,400 W. How much energy does it use in 30 min? KWh Need Help? Read It Submit Answer 13. [2/2 Points] DETAILS PREVIOUS ANSWERS OBINPHYS8 7.P.023. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Which costs more, running a 1,500-W hair dryer for 6 min or leaving a 70-W lamp on overnight (10 h)? the lamp the hair dryer Need Help? Read It Submit Answer 14. [-/2 Points] DETAILS OBINPHYS8 7.P.031. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER The resistance of an electric heater is 55 0 when connected to 120 V. How much energy does it use during 35 min of operation? Need Help? Read It Submit Answer 15. [2/2 Points] DETAILS PREVIOUS ANSWERS OBINPHYS8 8.Q.014. MY NOTES ASK YOUR TEACHER What would an audio speaker like that shown in the figure below do at the instant a low-voltage battery is connected to it? Voice coil Speaker cone VVVVV Battery in The speaker cone would only be pushed outward until the current stopped. The speaker cone would only be pulled inward until the current stopped. The speaker cone would either b outward or pulled inward until the current stopped. The speaker cone's motion is independent of the current and it would not move. Need Help? Read It Submit Answer 16. [-/2 Points] DETAILS OBINPHYS8 8.P.002. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER The generator at a power plant produces AC at 27,000 V. A transformer steps this up to 375,000 V for transmission over power ines. If there are 2,250 turns of wire in the input coil of the transformer, how many turns must there be in the output coil? turns Need Help? Read It Submit Answer 17. [-/2 Points] DETAILS OBINPHYS8 8.P.015. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER The blackbody radiation emitted from a furnace peaks at a wavelength of 1.6 x 1070 m (0.0000016 m). What is the temperature nside the furnace? Need Help? Read It Submit Answer 18. [2/2 Points] DETAILS PREVIOUS ANSWERS OBINPHYS8 8.Q.024. MY NOTES ASK YOUR TEACHER Which type of EM wave does your body emit most strongly? Radio waves. O Ultraviolet light. Visible light. . Infrared. Microwaves. Need Help? Read It Submit Answer 19. [-/2 Points] DETAILS OBINPHYS8 8.P.001. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER The charger cord used to recharge a cell phone contains a transformer that reduces 240 V AC to 5 V AC. For each 1,175 turns in the input coil, how many turns are there in the output coil? (Round your answer to at least one decimal place.) turns Need Help? Read It Submit Answer 20. [-/2 Points] DETAILS OBINPHYS8 8.P.005. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Compute the frequency (in MHz) of an EM wave with a wavelength of 2.2 in. (0.0559 m). MHz Need Help? Read It Submit
