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?

Explanation:

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 .

i had this question and the answer was 3.15 miles.

martina travels from school to her mom's office. from there, she walks to school. after school, she walks to the library and then to a friends house before finally ending back at home. find martina's total distance traveled.

a) 0 miles  

b) 0.4 miles  

c) 1 mile  

d) 3.15 miles

explanation:

wheres the pic