A. fixed volume, changeable shape.
-- The string is 1 m long. That's the radius of the circle that the mass is
traveling in. The circumference of the circle is (π) x (2R) = 2π meters .
-- The speed of the mass is (2π meters) / (0.25 sec) = 8π m/s .
-- Centripetal acceleration is V²/R = (8π m/s)² / (1 m) = 64π^2 m/s²
-- Force = (mass) x (acceleration) = (1kg) x (64π^2 m/s²) =
64π^2 kg-m/s² = 64π^2 N = about <span>631.7 N .
</span>That's it. It takes roughly a 142-pound pull on the string to keep
1 kilogram revolving at a 1-meter radius 4 times a second !<span>
</span>If you eased up on the string, the kilogram could keep revolving
in the same circle, but not as fast.
You also need to be very careful with this experiment, and use a string
that can hold up to a couple hundred pounds of tension without snapping.
If you've got that thing spinning at 4 times per second and the string breaks,
you've suddenly got a wild kilogram flying away from the circle in a straight
line, at 8π meters per second ... about 56 miles per hour ! This could definitely
be hazardous to the health of anybody who's been watching you and wondering
what you're doing.
Answer:
cm
Explanation:
= separation between the slits = 2783 x 10⁻⁹ m
= wavelength of coherent light = 644 nm = 644 x 10⁻⁹ m
= Distance of the screen = 6 cm = 0.06 m
= Position of nth bright fringe
Position of nth bright fringe is given as
for n = 2
m
for n = 4
m
Distance between 4th and 2nd bright fringes is given as
cm
Answer:
D. 12 cm
Explanation:
A node is a point on a standing wave that does not vibrate.
The nodes of a standing wave are shown in the following sketch.
The red dots are the nodes of the standing wave.
It is observed that the distance between two adjacent nodes is half the wavelength of the wave.
Therefore, if the wavelength of the wave is 24 cm, then the distance from one node to the net must be 24 / 2 = 12 cm.
Hence, choice D is the correct answer.
