Power is equal to the rate of energy usage, or work over time (W/t). It could also be consider Fd/t, since W=Fd.
Answer:
a) 
b) Efficiency=76.77%
Explanation:
a)
In order to solve this problem, we can use the following formula:
the problem provides us with all the necessary information so we can directly use the formula:
b) In order to find the efficiency, we can use the following formula:
so we get:
Efficiency=76.77%
When a person is making cardiovascular gains through aerobic activity they are increasing the amount of oxygen to the heart and lungs. This keeps the heart and lungs of a person very healthy. It decreases the chance of heart diseases.
Newton's second law tells you:
Sum of forces on an object = ma
Here, the forces acting on the bundle are the tension in the string and the force of gravity, these two must combine to yield the acceleration of the bundle.
So we have:
T-mg = ma
or T=m(g+a)
We know m=8.7kg, we need to find a from the information
starting from rest, an accelerating object covers distance according to:
<span>dist = 1/2 at^2 </span>
to cover 1m in 1.8s, we have:
a=2d/t^2 = 2x1/1.8^2 = 0.62 m/s/s
Thus, the tension in the string is:
<span>T = m(g+a)
= 8.7</span>kg(9.8m/s/s+0.62m/s/s)
<span>
<span>T = 90.654 N
</span>
I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!
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Answer:
Part a)
Part b)
t = 12 s
Explanation:
Part a)
Tension in the rope at a distance x from the lower end is given as
so the speed of the wave at that position is given as
here we know that
now we have
Part b)
time taken by the wave to reach the top is given as
