A wave with a period of 1⁄3 second has a frequency of D. 3 Hz. To
calculate this we will use the formula that represents the correlation
between a frequency (f) and a time period (T): T = 1/f. Or: f = 1/T. The
unit for the time period is second "s" while the unit for frequency is
Hertz "Hz" (=1/s). We know that T = 1/3 s. That means that f = 1/(1/3s) =
3 1/s = 3 Hz.
Answer:

Explanation:
wavelength 
d = 0.190 mm = 0.190 × 10⁻³ m
D = 1.91 m
By using the formula:


The first maximum will appear at an angle
from the beam axis
Answer:
The force must he apply to the sled is of F= 764.4 N.
Explanation:
m= 60 kg
g= 9.8 m/s²
μ=0.3
W= m*g
W= 588 N
Fr= μ*W
Fr= 176.4 N
F= W + Fr
F= 764.4 N
Because everybody in community needs to be smart & have some type of knowledge
1. Is 49.5
2. Is 8.6
4. Is 6.6
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