Answer: 0.25 seconds.
Explanation:
The yo-yo does 240 revolutions in one minute, and we know that one minute has 60 seconds, then the revolutions per second can be calculated as:
240 rev/60s = 4 rev/s, this will be the frequency of the yo-yo
The frequency is actually written as: f = 4 Hz = 4 s^-1
We want to find the period of this yo-yo.
The period is the duration of one cycle, and we have the relation:
f = 1/T
Where f is the frequency and T is the period, then:
T = 1/f
And we know the value of f, it is f = 4 s^-1
Then the period will be:
T = 1/(4 s^-1) = (1/4) s
Then the period of the yo-yo is 1/4 seconds = 0.25 seconds.
Answer:
Explanation:
This work done is in the form of Potential Energy so we'll use the formula of Potential Energy.
<u>Given Data:</u>
Mass = m = 250 kg
Acceleration due to gravity = g = 9.8 m/s²
Height = h = 6 m
<u>Required:</u>
Work Done in the form of Potential Energy = P.E. = ?
<u>Formula:</u>
P.E. = mgh
<u>Solution:</u>
P.E. = (250)(9.8)(6)
P.E. = 14700 Joules
![\rule[225]{225}{2}](https://tex.z-dn.net/?f=%5Crule%5B225%5D%7B225%7D%7B2%7D)
Hope this helped!
<h3>~AH1807</h3>
Answer:
b. 20%
Explanation:
Efficiency of an engine is a ratio in percentage of the work done to the energy intake of the engine.
η=(Q₁-Q₂)/Q₁×100%
η is efficiency, Q₁ is the energy intake, Q₂ is energy wasted.
The information provided is:
Energy intake = 400 J
Work done = 80 J = (400-320) =Q₁-Q₂
Energy wasted =320 J
η= 80/400×100%
=20%
