20W = 20 J/s
Energy expended during climbing stairs = 50 W of energy/stair = 50J/stair
For 20 stairs, Total energy = 50x20 = 1000 J
This can light bulbs for, T= 1000J/20 J/s =50 seconds
<span><u>Answer
</u>
The mass of 220 lb football has less than 288 lb football. So, it will be easier to move it since it will require less force. The heavy football will have a bigger momentum. Since 288 lb has more weight than 220 lb, it will have bigger inertia making it difficult for the players to stop it.
This makes it easier to tackle 220 lb football than 288 lb football.
</span>
Answer:
A, B, and E
Explanation:
The springs are identical, and are compressed the same amount, so they have the same initial elastic potential energy. (E is true)
Energy is conserved, so the darts have the same amount of kinetic energy. (A is true, C is false)
The lighter dart has the same energy as the heavier dart. Since it has less mass, it must have a greater speed. (B is true, D is false)
Since the two waves have equal amplitudes, if the crest of one wave
meets the trough of the other one, they'll add to produce a level of zero
at that location.
Hello.
The formula for Power is Work divided by Time; however, we do not have our value for Work - yet.
To find for the Work inputted, we need to use its formula: Force * Distance.
Let's multiply our Force by our Distance. Remember that our Force is always measured in Newtons (N), and our Distance is measured by Meters (M).
35,000 * 25 = 875,000 J (Unit for Work is "J" or "Joules")
Now that we have the value for Work, let's apply it to our Power formula.
P = 875,000 / 45; 19,444.44~
The Power required to lift the girder is 1944.44~ W (Unit for Power is "W" or "Watts").
I hope this helps!