Question

question 1
1 pts
what is power?
power is the amount of work you do.
power is the amount of work done in a certain amount of time.
power is the amount of work you are capable of doing.
power is the energy you expend over a certain amount of time.
question 2
1 pts
if it takes you 30 seconds to move a chair 20 meters across the floor, using a force of 5 newtons, how much power did you put out?
3.33 joules per second
120 joules per second
52 joules per second
3000 joules per second
question 3
1 pts
what is one watt equal to?
1 joule/second
1 m
1 newton x meter

Explanation:

Question 1

Power is defined as the rate at which work is done. The formula for power is \(P=\frac{W}{t}\), where \(W\) is work (in joules) and \(t\) is time (in seconds). Work is \(W = F\times d\) (force \(F\) times distance \(d\)). So power is the amount of work done in a certain amount of time.

First, calculate work \(W\). Using the formula \(W = F\times d\), where \(F = 5\space N\) and \(d=20\space m\). So \(W=5\times20 = 100\space J\). Then, use the power formula \(P=\frac{W}{t}\), with \(t = 30\space s\). So \(P=\frac{100}{30}\approx3.33\space J/s\).

By definition, the watt (\(W\)) is the SI unit of power. Since \(P=\frac{W}{t}\) (power \(P\), work \(W\), time \(t\)), and work \(W\) is in joules (\(J\)) and time \(t\) is in seconds (\(s\)), one watt is equal to 1 joule per second (\(1\space W=1\space J/s\)).

Answer:

Power is the amount of work done in a certain amount of time.

Question 2