2. A 5 Ohm resistor is connected to a 9 Volt battery. How many Joules of thermal energy are produced in 7 minutes?

3. The current in a flashlight powered by 4.5 Volts is 0.5 A. What is the power delivered to the flashlight?

4. If the flashlight in the previous problem is left on for 3 minutes, how much electric energy is delivered to the bulb?

7. A 50 Ohm resistance causes a current of 5 milliamps to flow through a circuit connected to a battery. What is the power in the circuit?

8. How many Joules of electric energy are delivered to a 60 Watt lightbulb if the bulb is left on for 2.5 hours?

Question

Physics

Peter Nixon

28 May, 02:02

2. A 5 Ohm resistor is connected to a 9 Volt battery. How many Joules of thermal energy are produced in 7 minutes?

3. The current in a flashlight powered by 4.5 Volts is 0.5 A. What is the power delivered to the flashlight?

4. If the flashlight in the previous problem is left on for 3 minutes, how much electric energy is delivered to the bulb?

7. A 50 Ohm resistance causes a current of 5 milliamps to flow through a circuit connected to a battery. What is the power in the circuit?

8. How many Joules of electric energy are delivered to a 60 Watt lightbulb if the bulb is left on for 2.5 hours?

+3

Answers (1)

Know the Answer?

Emmett Dougherty · Answer 1

2)

power of an electric device = V² / R where V is volts and R is resistance

putting given data

power = 9² / 5

= 16.2 J/s

energy produced in 7 minutes

= 16.2 x 7 x 60

= 6804J.

3) Power of an electrical device

= V² / R

= V X I where I is current

= 4.5 x. 5

= 2.25 W or J/s

4)

energy used in 3 minutes with power of 2.25 W

= 2.25 x 3 x 60

= 405 J.

7)

power of a electrical device

= V x I

IR x I where R is resistance.

= I²R

putting given data

power =.005² x 50

= 1.25 x 10⁻³ W.

8)

Energy used up by a 60 W bulb in 2.5 hours

= 60 x 2.5 x 60 x 60

= 5.4 x 10⁵ J.