Answer:
Option B - 360 J
Explanation:
One of the formulas used to find out how much work was done is :
E = 0.5×m×v² (where m is the mass and v is the velocity)
Now we substitute values from the question and simplify :
E = 0.5×500×1.2²
E = 250×1.2²
E = 250×1.44
E = 360 J
So our answer is Option B
Hope this helped and have a good day
Force D.
Gravity points downward.
Answer:
Explanation:
Radius of circular path of coin R = 12.5 x 10⁻²,
coefficient of static friction μs = .33
In order that the coin rotates in circular path , it requires centripetal force which is provided by friction. As speed of rotation increases , force of friction also increases to provide it required centripetal force. When the speed of rotation becomes too high so that frictional force can not compensate the increase in centripetal force then coin will start slipping or it starts moving with respect to turntable.
b ) At this point of time
centripetal force = limiting force of friction
mω² R = μs mg , m is mass of the coin , ω is angular velocity ,
ω² R = μs g
ω² x 12.5 x 10⁻², = .33 x 9.8
ω² = .33 x 9.8 / 12.5 x 10⁻²,
= 25.87
ω = 5.08 rad / s
2π / T = 5.08
T = 2π / 5.08
= 1.23 s .
Maybe there are some situations where speeds depend on wavelengths.
I don't know, and I can't say for sure that there aren't any at all.
But at least in the cases of electromagnetic waves and sound in air,
speeds don't depend on wavelength. All wavelengths of sound have
the same speed in air, and all electromagnetic wavelengths ... like heat,
radio, visible light, X-rays etc. ... have the same speed in vacuum.
If your wave is sound in air at sea level, then its speed is about 340 m/s .
If it's a radio wave, then its speed is about 300 million m/s .
Answer:
Resultant displacement is 240 feet west.
Explanation:
Consider that George starts at the origin of coordinates and walks to the left (west) to position 320 feet, then he turns around and walks to the right (east) for 80 feet.So he is now (320 - 80 = 240) feet from the origin but still to the left of it. This means he is 240 feet west from where he started.
