Answer:
5 .07 s .
Explanation:
The child will move on a circle of radius r
r = 1.5 m
Let the velocity of rotation = v
radial acceleration = v² / r
v² / r = 2.3
v² = 2.3 r = 2.3 x 1.5
= 3.45
v = 1.857 m /s
Time of revolution = 2π r / v
= 2 x 3.14 x 1.5 / 1.857
= 5 .07 s .
The force on the fry is 
Explanation:
We can find the force acting on the fry by using Newton's second law:

where
F is the net force on the fry
m is its mass
a is its acceleration
For the fry in this problem,


Therefore, the force exerted on the fry is

Learn more about Newton's second law here:
brainly.com/question/3820012
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Answer:
a loud explosive noise caused by the shock wave from an aircraft traveling faster than the speed of sound.
Explanation:
In 1 hour, the hour hand sweeps across 1/12 of the clock's face. In 40 min, the hour hand travels (40 min)/(60 min) = 2/3 of the path it covers in an hour, so a total of 1/12 × 2/3 = 1/18 of the clock's face. This hand traces out a circle with radius 0.25 m, so in 40 min its tip traces out 1/18 of this circle's radius, or
1/18 × 2<em>π</em> (0.25 m) ≈ 0.087 m
The minute hand traverses (40 min)/(60 min) = 2/3 of the clock's face, so it traces out 2/3 of the circumference of a circle with radius 0.31 m:
2/3 × 2<em>π</em> (0.31 m) ≈ 1.3 m
The second hand completes 1 revolution each minute, so in 40 min it would fully trace the circumference of a circle with radius 0.34 m a total of 40 times, so it covers a distance of
40 × 2<em>π</em> (0.34 m) ≈ 85 m
Answer:

Explanation:
The formula for the single-slit diffraction is

where
y is the distance of the n-minimum from the centre of the diffraction pattern
D is the distance of the screen from the slit
d is the width of the slit
is the wavelength of the light
In this problem,


, with n=2 (this is the distance of the 2nd-order minimum from the central maximum)
Solving the formula for d, we find:
