Water flows along a streamline down a river of constant width. Over a short distance, the water slows from speed v to v/3. Which
of the following can you correctly conclude about the river's depth? a. It became deeper by a factor of 3.
b. It became shallower by a factor of 3.
c. It became deeper by a factor of 3^2
d. It became shallower by a factor of 3^2
The complete question is how much heat energy is delivered by the iron in 30 seconds. Heat is given by IVt, Where I is the current in Amperes, V is the voltage, and t is the time in seconds, Therefore; Heat energy = 120 × 10 ×30 = 36000 joules or 36 kJ Heat energy is measured in joules.