Two light bulbs, b1 and b2, are connected to a battery having appreciable internal resistance as shown in the figure. what happens to the brightness of bulb b1 when we close the switch s? . . a. the brightness of b1 does not change.. b. the brightness of b1 increases permanently.. c. the brightness of b1 decreases permanently.. d. the brightness of b1 increases temporarily but gradually decreases back to its original brightness.. e. the brightness of b1 decreases temporarily but gradually increases back to its original brightness.

When we close the switch S, what happens to the brightness of bulb B1 is the brightness of B1 decreases permanently.

Two light bulbs, B1 and B2, are connected to a battery having appreciable internal resistance as shown in the figure. What happens to the brightness of bulb B1 when we close the switch S?

Internal resistance is a practical electrical power source which is a linear electric circuit may be represented as an ideal voltage source in series with an impedance.

Internal resistance is measured in Ohms. The relationship between internal resistance (r) and emf (e) of cell s is

Where, e = EMF i.e. electromotive force (Volts), I = current (A), R = Load resistance, and r is the internal resistance of cell measured in ohms.

When we close the switch S, what happens to the brightness of bulb B1 is the brightness of B1 decreases permanently. Whereas the brightness of B2 which is located near the switch is increases permanently.

Grade:  9

Subject:  physics

Chapter:  electricity

Keywords: light bulbs, brightness, battery, physics, battery

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg