Answer: Negatively charged particles are repelled by other negatively charged particles
Explanation:
KE = ½mv² = ½(4.00 kg)(16.0 m/s)² = 512 J
A) 750 m
First of all, let's find the wavelength of the microwave. We have
is the frequency
is the speed of light
So the wavelength of the beam is

Now we can use the formula of the single-slit diffraction to find the radius of aperture of the beam:

where
m = 1 since we are interested only in the central fringe
D = 30 km = 30,000 m
a = 2.0 m is the aperture of the antenna (which corresponds to the width of the slit)
Substituting, we find

and so, the diameter is

B) 0.23 W/m^2
First we calculate the area of the surface of the microwave at a distance of 30 km. Since the diameter of the circle is 750 m, the radius is

So the area is

And since the power is

The average intensity is

The net force on the sledge is 31.64N.
Frictional force = µkR
= 0.269 x 42.2 x 9.81 = 111.36
net force = 143N - 111.36N
= 31.64N
refer brainly.com/question/24557767
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It depends on where the cat is applying the force and how much the force is .. after all where and at what is distance from the axis of rotation of the door