Answer:
0
Explanation:
Forces with equal magnitudes and opposite directions cancel each other out, so the net force is 0.
She is traveling at a constant speed.
Answer:
The difference between the cost of operating LED and incandescent bulb is $5.1
Explanation:
We are given the cost of electricity that is 12.75 cents per kWh. We want to find out the difference in the operating cost of an incandescent and LED bulb for a time period of 2,000 hours.
Since we are not given the rating of the incandescent bulb and LED bulb, we will assume their ratings.
For a light intensity of 250 Lumens;
The average rating of an LED bulb is approximately 5 Watts.
The average rating of an incandescent bulb is approximately 25 Watts.
Now lets find out the kWh of each bulb.
Energy = Power×Time
For LED bulb:
E = 5×2,000 = 10,000 Wh
Divide by 1000 to convert into kWh
E = 10,000/1000 = 10 kWh
Cost = 12.75×10 = 127.5 cents
Cost = $1.27
For Incandescent bulb:
E = 25×2,000 = 50,000 Wh
Divide by 1000 to convert into kWh
E = 50,000/1000 = 50 kWh
Cost = 12.75×50 = 637.5 cents
Cost = $6.37
Difference in Cost:
Difference = $6.37 - $1.27 = $5.1
Therefore, the difference between the cost of operating LED and incandescent bulb is $5.1.
