A4-m × 5-m × 6-m room is to be heated by a base-board resistance heater. it is desired that the resistance heater be able to raise the air temperature in the room from 5 to 25°c within 17 min. assuming no heat losses from the room and an atmospheric pressure of 100 kpa, determine the required power of the resistance heater. assume constant specific heats at room temperature.

Agymnast dismounts off the uneven bars in a tuck position with a radius of 0.3m (assume she is a solid sphere) and an angular velocity of 2rev/s. during the dismount she stretches out into the straight position, with a length of 1.5m, (assume she is a uniform rod through the center) for her landing. the gymnast has a mass of 50kg. what is her angular velocity in the straight position?

Identify the theory that can be used to explain each phenomenon. answers diffraction: wave theory interference: wave theory reflection: both particle and wave theories refraction: both particle and wave theories

Achild has maximum walking speed of 1.6 m/s. what is the length of the child's legs? 0.26 m