Explanation:
The net force along the horizontal direction is

where f is the frictional force. We can find the frictional force by looking at the vertical forces acting on the couch:

From the definition of frictional force,


Therefore, the net force on the couch is

__Protons and neutrons have similar mass.
__Electrons are smaller than a proton or a neutron.
Explanation:
The three particles involved in this problem are:
- Proton: it is positively charge, it is found in the nucleus of the atom, and its mass is

- Neutron: it has no electric charge, it is also found in the nucleus of the atom, and its mass is approximately equal to that of the proton (just slightly larger)
- Electron: it has negative electric charge, it orbit around the nucleus of the atom, and its mass is much smaller than that of the proton:

We can now analyze each of the given statement:
__Protons and neutrons have similar mass. --> TRUE
__Protons and electrons have similar mass. --> FALSE, the electron is much lighter
__Neutrons and electrons have similar mass. --> FALSE, the neutron is much heavier
__Protons are smaller than a neutron or an electron. --> FALSE, protons are similar to the neutrons
__Neutrons are smaller than a proton or an electron. --> FALSE, neutrons are similar to the protons
__Electrons are smaller than a proton or a neutron. --> TRUE
Learn more about atoms:
brainly.com/question/2757829
#LearnwithBrainly
B force i belive becuase when is done it force
Answer:
73325J
Explanation:
Given parameters:
Mass of water = 0.5kg
Initial temperature = 30°C
Final temperature = 65°C
Specific heat capacity = 4190J/kg°C
Unknown:
Amount of energy absorbed = ?
Solution:
The amount of energy absorbed can be derived using the expression below;
H = m c Δt
H is the amount of energy
m is the mass
c is the specific heat
Δt is the change in temperature
H = 0.5 x 4190 x (65 - 30 )
H = 73325J
The Moon is 3.8 108 m from Earth and has a mass of 7.34 1022 kg. 5.97 1024 kg is the mass of the Earth.
<h3>What kind of gravitational pull does the moon have on the planet?</h3>
On the surface of the Moon, the acceleration caused by gravity around 1.625 m/s2 which is 16.6% greater than on the surface of the Earth 0.166.
<h3>What does the Earth's center's gravitational pull feel like?</h3>
Gravity is zero if you are in the centre of the earth since everything around you is pulling "up" (up is the only direction).
<h3>Where is the Earth's and the moon's gravitational centre?</h3>
It is around 1700 kilometres below Earth's surface.
To know more about gravitational force visit:-
brainly.com/question/12528243
#SPJ4