Physics-Voltage Quesiton?

Question

When a voltage of 4.5V is applied across a lightbulb,a current of 120mA passes thru its filament. What is the resistnace of the bulb and the power disappated in it?

I have no thoughts on where to begin on this one.

I WILL chose a BEST ANSWER....

Answer 1

V = IR (Ohm's Law)
R = V / I
R = (4.5) / (.120)
R = 38 Ω

P = IV
P = (.120)(4.5)
P = 0.54 W

Answer 2

Buoyant rigidity is desperate by using the formula B=PVg the place... B is the rigidity upwards V is the quantity of the liquid displaced. g is the acceleration by way of gravity of the earth. Likewise, it is comparable to the load of the liquid displaced. anticipate g became under it is on earth. you're able to have much less rigidity pushing you upwards. in spite of if, likewise, on the grounds that your downward rigidity is equivalent on your mass situations acceleration (i.e. gravity of the planet), and the gravity pulling you down is far less as properly, the two effects could in actuality not count. while it comes all the way down to it the only element that concerns is the ratio of the densities of the element you are trying to waft. Edit: Sorry, P interior the unique formula became density. i'm too drained and could be examining for my physics very final day after today.

Answer 3

Try I=V/R
where I is the current, V is the potential difference, and R is a proportionality constant called the resistance

Answer 4

Use Ohm's law:

V = IR

You know the voltage(V) and the current (I).

Solve for the resistance (R).

Aloha

Answer 5

THEN...........,
try Power (watts) = V*I