Answer:
C
Explanation:
If a pulley system has an efficiency of 74.2%, then only that fraction of the work performed will be useful. 74.2%=0.742. 0.742*200 is about 148J. Hope this helps!
Answer:
A. 1.71 m
B. 2.66 m
Explanation:
A. Determination of the height of the pier.
We'll begin by calculating the time taken for the ball to get to the water
This can be obtained as follow:
Horizontal velocity (u) = 1.27 m/s,
Horizontal distance (s) = 0.75 m
Time (t) =?
s = ut
0.75 = 1.27 × t
Divide both side by 1.27
t = 0.75 / 1.27
t = 0.59 s
Finally, we shall determine the height of the pier as follow:
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) = 0.59 s
Height of pier (h) =?
h = ½gt²
h = ½ × 9.8 × 0.59²
h = 4.9 × 0.3481
h = 1.71 m
Thus, the height of the pier is 1.71 m
B. Determination of the horizontal distance.
Horizontal velocity (u) = 4.50 m/s
Time (t) = 0.59 s
Horizontal distance (s) =?
s = ut
s = 4.5 × 0.59
s = 2.66 m
Thus, if the ball moved at a velocity of 4.50 m/s off the pier, it will land at a distance of 2.66 m from the end of the pier.
The two possible distances that you might infer your friends swam while the lights were out are 25 m and 75 m.
Answer:
Explanation:
So you have to measure the distance covered by your friend in a time gap of 86 s. And the average velocity is given as 0.29 m/s.
Then as per the mathematical calculation of velocity, distance can be measured as the product of velocity with time interval.
Distance = Velocity × Time Interval
Distance = 0.29 m/s×86 s = 24.94 m.
So based on this calculation, one of the possible distance inferred by you will be 24.94 m.
Another possible distance can be guessed from the statements provided. So if the length of pool is 50 m, then covering halfway in opposite direction to his starting direction means completion of one full length i.e., 50 m and then halfway of that 50 m which is 25m, so totally 50 +25 = 75 m.
So in other way, we can assume that your friend has covered 75 m distance during the light out.
Thus, the two possible distances that you might infer your friends swam while the lights were out are 25 m and 75 m.
We will calculate the synodic period, as it is the time it takes for the object to reappear at the same point in the sky with respect to the sun, when viewed from Earth. For this problem we will apply the concepts related to the orbital period ( Kepler's Third Law ) which is determined as
Where,
r = Radius/Distance
G = Gravitational Universal Constant
m = Mass of the object
Replacing,