c.magnetic induction hope this helps
The answer yr looking for would b true!
The law states that external forces cause objects to accelerate, and the amount of acceleration is directly proportional to the net force and inversely proportional to the mass of the object.
If you can’t copy and paste it just reword it
<span>ΔT for the first sample is the total samples final temp, minus the first sample's initial temp (47.9-22.5), so 25.4oC.
Calculating q for the first sample as 108g x 4.18 J/g C x 25.4oC = 11466.58 Joules
Figuring that since the first sample gained heat, the second sample must have provided the heat, so doing the calculation for the second sample, I used
q=mCΔT
11466.58 Joules = 65.1g x 4.18 J / g C x ΔT
11466.58/(65.1gx4.18)=ΔT
ΔT=42.14oC
So, since second sample lost heat, it's initial temperature was 90.04oC (47.9oC final temperature of mixture + 42.14oC ΔT of second sample).</span>
Answer:
This is an incomplete question. The complete question is --
An individual white LED (light-emitting diode) has an efficiency of 20% and uses 1.0 W of electric power.
How many LEDs must be combined into one light source to give a total of 3.8W of visible-light output (comparable to the light output of a 100W incandescent bulb)?
And the answer is --
19 LEDs
Explanation:
The full form of LED is Light emitting diode.
It is given that the efficiency of the LED bulb is 20 %
1 LED uses power = 1 W
So the output power of 1 LED = 0.2 W
We need to find the power required to give a 3.8 W light.
Power required for 3.8 W = Number of LEDs required = (total required power / power required for 1 LED )
= 3.8 / 0.2
= 19
Therefore, the number of LEDs required is 19.