Answer:
Explanation:
Sam mass=75kg
Height is 50m
20° frictionless slope
Horizontal force on Sam is 200N
According to the work energy theorem, the net work done on Sam will be equal to his change in kinetic energy.
Therefore
Wg - Ww =∆K.E
Note initial the body was at rest at top of the slope.
Then, ∆K.E is K.E(final) - K.E(initial)
K.E Is given as ½mv²
Since initial velocity is zero then, K.E(initial ) is zero
Therefore, ∆K.E=½mVf²
Wg is work done by gravity and it is given by using P.E formulas
Wg=mgh
Wg=75×9.8×50
Wg=36750J
Ww is work done by wind and it's is given by using formulae for work
Work=force × distance
Ww=horizontal force × horizontal distance
Using Trig.
TanX=opposite/adjacent
Tan20=h/x
x=h/tan20
x=50/tan20
x=137.37m
Then,
Ww=F×x
Ww=200×137.37
We=27474J
Now applying the formula
Wg - Ww =∆K.E
36750 - 27474 =½×75×Vf²
9276=37.5Vf²
Vf²=9275/37.5
Vf²= 247.36
Vf=√247.36
Vf=15.73m/s
Answer:
B.The linear velocity of the gears is the same. The linear velocity is 432π centimeters per minute.
Explanation:
As we know that the small gear completes 24 revolutions in 20 seconds
so the angular speed of the smaller gear is given as


Now we know that the tangential speed of the chain is given as

so we have



Since both gears are connected by same chain so both have same linear speed and hence correct answer will be
B.The linear velocity of the gears is the same. The linear velocity is 432π centimeters per minute.
B Protons and neutrons. Electrons are outside the nucleus.
I’m not entirely certain, but usually, spring symbolizes rebirth.
Answer:
5
Explanation:
The light intensity may be defined as the strength of the light or the magnitude of its brightness that a source of light can produce.
The light threshold is the minimum intensity of the light that our eye can detect and the ability to adapt to darkness.
In the context, Daniel wishes to find if can notice the difference in the intensity of the light when he add 5 candles to the set of 50 candles.
He noticed that when he added 5 candles, he could notice the difference in the intensity and when he added less than 5 candles to the set of 50 candles he could not detect.
Thus, the difference threshold for Daniel to detect the change in the intensity of the light is 5 candles.