Answer:
Explanation:
ignoring air resistance, the kinetic energy at water impact will equal the potential energy converted
½mv² = mgh
v = √(2gh)
v = √(2(9.81)2.1) = 6.4188... m/s
after impact, an impulse will result in a change of momentum.
There is a downward impulse due to gravity equal to the weight of the stone and an upward average force due to water resistance and buoyancy force.
FΔt = mΔv
(F - mg)Δt = m(vf - vi)
(F - mg) = m(vf - vi)/Δt
F = m(vf - vi)/Δt + mg
F = m((vf - vi)/Δt + g)
F = 1.05(((½(-6.4188) - -6.4188)/ 1.83) + 9.81)
F = 12.14198...
F = 12.1 N
<span>The correct answer is option C. i.e.Equilateral triangles. All equilateral triangle have equal sides. Due to this these set of shapes will always be similar. Similarity in the sense that only the size of the triangles can change to large or smaller but the shape will be be similar always.</span>
Answer: Metal. There are six of them. inclined plane, the wedge, the screw, the lever, the wheel and axle, and the pulley.
Hope this helps!
~Jarvis
Explanation:
Answer is D - five.
<em>Explanation;</em>
- Electron dot diagrams show the valence electrons around the element by using dots.
- Valence electrons are the electrons which are in outermost shell of the atom.
-The atomic number of the N atom is 7.
Atomic number = number of protons = 7
If the atom is neutral,
number of protons = number of electrons.
Hence, N atom has 7 electrons.
- The electron configuration is 1s² 2s² 2p³.
Hence, N atom has 2 + 3 = 5 valence electrons. So, five electrons are represented in electron dot diagram of N.
Answer:
<em>h = 20 m</em>
Explanation:
<u>Gravitational Potential Energy</u>
Gravitational potential energy (GPE) is the energy stored in an object due to its vertical position or height in a gravitational field.
It can be calculated with the equation:
U=m.g.h
Where m is the mass of the object, h is the height with respect to a fixed reference, and g is the acceleration of gravity or 
.
The weight of an object of mass m is:
W = m.g
Thus, the GPE is:
U=W.h
Solving for h:
The weight of the owl is W=40 N and its GPE is U=800 J.
h = 20 m
