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A resistor whose value R=10┬а╬й is connected to a 10-volt battery. What will be the power P and the amount of heat H generated in one minute?
P=100┬аW,H=6000┬аJ
P=1┬аW,H=60┬аJ
P=20┬аW,H=1200┬аJ
P=10┬аW,H=600┬аJ
P=10┬аW,H=600┬аJ
To find the power and heat, we use the basic formulas for electrical power and energy. Power (P) is the rate of energy dissipation, calculated as P=RV2тАЛ. Heat (H) is the total energy dissipated over time (t), calculated as H=P├Чt.
To find the power and heat, we use the basic formulas for electrical power and energy. Power (P) is the rate of energy dissipation, calculated as P=RV2тАЛ. Heat (H) is the total energy dissipated over time (t), calculated as H=P├Чt.
Think of a light bulb: a 10-watt bulb consumes energy at a rate of 10 joules every second. If you keep it on for a minute, it will have used 600 joules of electrical energy to produce light and heat.
P=RV2тАЛ тАФ Formula for Power dissipated in a resistor
H=P├Чt тАФ Formula for Heat generated over time
When a voltage (V) is applied across a resistor (R), a current (I=RVтАЛ) flows through it. The resistor dissipates this electrical energy as heat according to Joule's Law. With V=10V and R=10╬й, the power is P=10102тАЛ=10W. Over one minute (t=60s), the total heat generated is H=10W├Ч60s=600J.
Voltage V=10V and Resistance R=10╬й
Time t=1minute=60seconds
Power unit is Watt (W) and Heat/Energy unit is Joule (J)
Electrical heating appliances like toasters and heaters
Calculating efficiency and energy consumption of circuits
The SI unit of power is the Watt (1W=1J/s).
Option A is incorrect as 100W exceeds the calculated power.
Option B is incorrect as 1W is too low.
Option C is incorrect as the values do not match the calculation (P=10W,H=600J).
D is correct тАФ The power dissipated is 10W and the heat generated in 60 seconds is 600J.
Always convert time into standard SI units (seconds) before calculating energy/heat in Joules.