Answer:
<em>P = 66.67 W</em>
Explanation:
<u>Joule Heating</u>
It's the process by which the electric current passing through a conductor produces heat.
Also known as Joule's first law or the Joule–Lenz law, states that the power of heating generated by an electrical conductor (P) is proportional to the product of its resistance (R) and the square of the current (I).
It can be described by the equation that follows:
Also, we can calculate the voltage V with the formula of Ohm's law:
Combining both equations, power can be related to the voltage:
Given the power and the voltage, the resistance can be calculated by solving for R:
There are two bulbs marked P=200W V=250V and P=100 W V=250.
The first bulb has a resistance of:
The first bulb has a resistance of:
When connected in series, the total resistance is
The total power consumed when connecting them to a V=250 V supply is:
P = 66.67 W
Answer:
Option B is correct.
Explanation:
The resistance of a material or wire is represented by the formula below.
R=(ρL)/A
where
- R is resistance of wire
- ρ is the resistivity of the material
- A is the cross sectional area of wire
- L is length of wire
Resistance increases with increase in length and resistivity which means options C and D are wrong.
A=(π
)/4
An increase in diameter will result in a proportional increase in area
From the resistance formula, an increase in area will cause a reduction in the resistance of the material.Thus increased diameter of wire will lower the resistance of wire. Option B is correct
Have a great day
Answer:
666.6 seconds
Explanation:
if he runs at 3m/sec he will achieve the goal of 2000m in 666.6 seconds. just divide - 3/2000.
note we have changed 2km to 2000metres
Answer:
0 Kelvin
Explanation:
Atoms in absolute temperature get approximatelly motionless since 0 Kelvin is -273 degrees Celcius. The kinetic energy of atoms/particles in matter has the possible lowest value ( almost zero), so that there is nothing colder than 0 Kelvin.
