An electric heater has a resistance of 50\(\Omega\). When it is immersed in water and connected to mains source, it draws a current of 4.0A. Calculate the h...
Question 1 Report
An electric heater has a resistance of 50\(\Omega\). When it is immersed in water and connected to mains source, it draws a current of 4.0A. Calculate the heat gained by the water if the heater is switched on for 2 minutes, assuming no heat losses to the surroundings
Answer Details
The heat gained by the water can be calculated using the formula:
Heat = Power × Time
where Power = Current × Voltage and Time = 2 minutes = 120 seconds
The voltage can be calculated using Ohm's law:
Voltage = Current × Resistance
Substituting the values given:
Voltage = 4.0A × 50\(\Omega\) = 200V
Therefore, Power = 4.0A × 200V = 800W
Substituting the values in the formula:
Heat = Power × Time = 800W × 120s = 96,000J
Therefore, the heat gained by the water is 96,000J.
The correct option is (d) 96,000J.
Download The App On Google Playstore
Everything you need to excel in your exams
Personalized AI Learning Chat Assistant
200,000+ Exam Questions Across IGCSE, JAMB, WAEC & NECO
Over 3,900 Lesson Notes
Offline Support - Learn Anytime, Anywhere
Green Bridge Timetable
Literature Summaries & Potential Questions
Track Your Performance & Progress
In-depth Explanations for Comprehensive Learning