M, mass=84 kg
height, h=3.9m
gravity, g= 9.8m/s2
W = F . d
F=force
d=Displacement
W=work done by force
Now by putting the values
F= m g (Acting downward )
d= h (Upward)
W= m g h ( work done against the force)
W= 84•9.8•3.9J
W= 3210.48
Therefore the answer will be 3210.48J.
Answer:
The dog catches up with the man 6.1714m later.
Explanation:
The first thing to take into account is the speed formula. It is
, where v is speed, d is distance and t is time. From this formula, we can get the distance formula by finding d, it is 
Now, the distance equation for the man would be:

The distance equation for the dog would be obtained by the same way with just a little detail. The dog takes off running 1.8s after the man did. So, in the equation we must subtract 1.8 from t.

For a better understanding, at t=1.8 the dog must be in d=0. Let's verify:

Now, for finding how far they have each traveled when the dog catches up with the man we must match the equations of each one.






The result obtained previously means that the dog catches up with the man 3.8571s after the man started running.
That value is used in the man's distance equation.


Finally, the dog catches up with the man 6.1714m later.
Answer:
<h2>a) 50°</h2><h2>b) 40°</h2>
Explanation:
Check the complete diagram n the attachment below
a) The angle of incidence on a plane surface is the angle between the incidence ray and the normal ray acting on a plane surface. The normal ray is the ray perpendicular to the surface while the incidence ray is the ray striking a plane surface.
According to the diagram, the angle of reflection r₂ on M₂ is 90°-g where g is the angle of glance.
Given angle of glance on M₂ to be 40°, r₂ = 90-40 = 50°
According the second law of reflection, the angle of incidence = angle of reflection, therefore i₂ = r₂ = 50° (on M₂)
Also ∠OO₂O₁ = ∠OO₁O₂ = 40° (angle of glance on M₁){alternate angle}
The angle of incidence on M₁ = 90° - 40° = 50°
b) The angle of incidence to the surface of M₁(∠PO₁A)will be the angle of glance on M₁ which is equivalent to 40°
<h3><u>Answer;</u></h3>
Electron cloud
<h3><u>Explanation;</u></h3>
- <em><u>An atom is the smallest particle of an element that can take part in a chemical reaction. Atom is made up of two parts ; that is the nucleus and the electron cloud. The nucleus contain subatomic particles; protons and neutrons, while the electron cloud contains the electrons.</u></em>
- <em><u>The electron cloud is the largest part of the atom and is mostly an empty space. Most of an atom is a cloud of electrons surrounding a space called the nucleus with tiny protons and neutrons.</u></em>
Answer:
0.28802
2.57162 W
14.28 W
53.55 W
6.07142 W
Explanation:
R = 280Ω
L = 100 mH
C = 0.800 μF
V = 50 V
ω = 10500rad/s
For RLC circuit impedance is given by

Power factor is given by

The power factor is 0.28802
The average power to the circuit is given by

The average power to the circuit is 2.57162 W
Power to resistor

Power to resistor is 14.28 W
Power to inductor

Power to the inductor is 53.55 W
Power to the capacitor

The power to the capacitor is 6.07142 W