Answer: C. 20J
Explanation: im pretty sure sorry if im wrong :(
You are pulling with 57 N on a heavy bookshelf, but the bookshelf doesn't move. What is the force of static friction in Newtons acting on the bookshelf?
Answer:
57N
Explanation:
Since the bookshelf isn't moving, the force you're exerting on the shelf must be equal to the force of static friction
So the force of static friction is 57N
Questlon 6 of 10
In these magnets, why do the poles closest to each other attract?
S
S
O A. The magnetic field is stronger between two like magnetic poles.
B. The magnetic fields of the two magnets repel each other.
C. The opposite poles of the two magnets push the magnets
together.
D. The two poles closest to each other are opposite magnetic poles.
Answer:
The two poles closest to each other are opposite magnetic poles
Explanation:
Just took the test
Answer:
its all of them
Explanation:
Sal is experimenting with materials that dissolve in water. He finds a material that dissolves well in water. Which of these could it
be?
any pics? so i can see the question ⁉️
Philosophy: The Big Picture Unit 8
Would an existentialist argue that the study of philosophy was a good use of a life?
A. Yes, if society valued the results of the study.
B. Yes, but only if the individual found it meaningful.
C. No, a life should be spent minimizing the role of anxiety.
D. No, there is no way that philosophy could create a meaningful life.
1 kg block slides down a frictionless inclined plane that makes an angle of 300 with respect to the ground. The total length of the plane is 2 m, but midway down it collides with a second block, weighing 0.5 kg. The two blocks stick together and travel as one unit the rest of the way down the ramp. What is the kinetic energy of the combined 1.5 kg block when it reaches the bottom of the plane
Answer:
the kinetic energy of the combined 1.5 kg block when it reaches the bottom of the plane is 10.62 J
Explanation:
Given that the data in the question;
angle of inclination with respect to the ground [tex]\theta[/tex] = 30°
length of plane d = 2m
m₁ = 1 kg
m₂ = 0.5 kg
now, velocity of the first block at midpoint;
[tex]\frac{1}{2}[/tex]mv² = mgsin[tex]\theta[/tex][tex]\frac{d}{2}[/tex]
[tex]\frac{1}{2}[/tex]v² = gsin[tex]\theta[/tex][tex]\frac{d}{2}[/tex]
v² = gsin[tex]\theta[/tex]d
v = √( gsin[tex]\theta[/tex]d)
g is 9.8 m/s
so we substitute
v = √( 9.8 × sin30° × 2)
v = √( 19.6 )
v = 3.13 m/s
Now, velocity just after collision of the blocks will be;
(m₁ + m₂)v₂ = m₁v
v₂ = m₁v / (m₁ + m₂)
we substitute
v₂ = (1 × 3.13) / (1 + 0.5)
v₂ = 3.13 / 1.5
v₂ = 2.0866 m/s
now, final kinetic energy will be;
[tex]KE_f[/tex] = (m₁ + m₂)gsin[tex]\theta[/tex][tex]\frac{d}{2}[/tex] + Initial Kinetic energy
[tex]KE_f[/tex] = (m₁ + m₂)gsin[tex]\theta[/tex][tex]\frac{d}{2}[/tex] + [tex]\frac{1}{2}[/tex]mv₂²
we substitute
[tex]KE_f[/tex] = [(1 + 0.5)9.8 × sin30 × [tex]\frac{2}{2}[/tex]] + [[tex]\frac{1}{2}[/tex] × 1.5 × 2.0866 ]
[tex]KE_f[/tex] = 7.35 + 3.2654
[tex]KE_f[/tex] = 10.62 J
Therefore, the kinetic energy of the combined 1.5 kg block when it reaches the bottom of the plane is 10.62 J
How do scientists know the continents were once closer than they are today? Explain your answer in 2-3 complete sentences.
Answer:
Continental drift describes one of the earliest ways geologists thought continents moved over time. Today, the theory of continental drift has been replaced by the science of plate tectonics.
The theory of continental drift is most associated with the scientist Alfred Wegener. In the early 20th century, Wegener published a paper explaining his theory that the continental landmasses were “drifting” across the Earth, sometimes plowing through oceans and into each other. He called this movement continental drift.
How are the particles in matter organized
Answer:
Particles in agas are well separated with no regular arrangement. liquid are close together with no regular arrangement. solid are tightly packed, usually in a regular pattern.
Explanation:
hope this helps
Particle track detectors are used to measure the speed of particles if the lifetime of the particle is known. Particle-X has a lifetime of 256.2 ps. These particles are created in an experiment inside the detector by a given reaction. The particles leave 10.7 cm long tracks on average before they decay into other particles not observable by the detector. What is the average speed of the particles in terms of the speed of light
Answer:
the average speed of the particles in terms of the speed of light is 0.81c
Explanation:
Given the data in the question;
[tex]t_p[/tex] = 256.2 ps = 256.2 × 10⁻¹² s
speed of light c = 2.99 × 10⁸ m/s
d = 10.7 cm = 0.107 m
we know that; Average speed v = d/t ------- let this be equation 1
Also, given that 256.2 ps is the lifetime of particle X frame, proper time will be;
t = Y[tex]t_p[/tex] = [tex]t_p[/tex] / √( 1 - [tex]\frac{v^2}{c^2}[/tex] ) --------- let this be equation 2
Next, we input equation 2 into equation 1'
v = d / [ [tex]t_p[/tex] / √( 1 - [tex]\frac{v^2}{c^2}[/tex] ) ]
v = d/[tex]t_p[/tex][ √( 1 - [tex]\frac{v^2}{c^2}[/tex] ) ]
v[tex]t_p[/tex]/d = √( 1 - [tex]\frac{v^2}{c^2}[/tex] )
we square both sides
( v[tex]t_p[/tex]/d )² = (√( 1 - [tex]\frac{v^2}{c^2}[/tex] ) )²
v²[tex]t_p[/tex]²/d² = 1 - [tex]\frac{v^2}{c^2}[/tex]
v²[tex]t_p[/tex]²/d² + [tex]\frac{v^2}{c^2}[/tex] = 1
v²( [tex]t_p[/tex]²/d² + [tex]\frac{1}{c^2}[/tex] ) = 1
v²( ([tex]t_p[/tex]²c² + d²)/d²c² ) = 1
∴
v² = (d²c²) / ([tex]t_p[/tex]²c² + d²)
v = √[ (d²c²) / ([tex]t_p[/tex]²c² + d²) ]
v = (dc) / √([tex]t_p[/tex]²c² + d²)
so we substitute
v = (0.107 m × c) / √( (256.2 × 10⁻¹² s)²(2.99 × 10⁸ m/s)² + (0.107 m )²)
v = 0.107c / √( 0.00586814 + 0.011449 )
v = 0.107c / √( 0.01731714 )
v = 0.107c / 0.1315946
v = 0.81c
Therefore, the average speed of the particles in terms of the speed of light is 0.81c
Calculate the speed of an object that travels 75m in 15s.
Answer:
5m/s
Explanation:
speed=distance/time
=75/15
=5m/s
A car has a mass of 1200 kg and a velocity of 14 m/s. Calculate the
momentum of the car.
Answer:
p = 16,800
Explanation:
Two ice skaters, with masses of 40.0 kg and 65.0 kg , are at the center of a 50.0 m -diameter circular rink. The skaters push off against each other and glide to opposite edges of the rink. Part A If the heavier skater reaches the edge in 10.0 s , how long does the lighter skater take to reach the edge
Answer:
6.15 s
Explanation:
From the question,
Applying the law of conservation of momentum
Momentum of the Heavier skater = Momentum of the lighter skater.
Mv = mV................. Equation 1
Where M = mass of the heavier skater, m = mass of the lighter skater, v = Velocity of heavier skater, V = velocity of the lighter skater.
But,
v = r/t........................ Equation 2
V = r/t'................ Equation 3
Where r = radius of the circular rink, t = time taken for the heavier skater to reach the edge, t' = time taken for the lighter skater to reach the edge.
Substitute equation 2 and equation 3 into equation 1
M(r/t) = m(r/t')............. Equation 4
Given: M = 65 kg, m = 40 kg, r = 50/2 = 25 m, t = 10 s.
Substitute into equation 4 and solve for t'
65(25/10) = 40(25/t')
162.5 = 1000/t'
t' = 1000/162.5
t' = 6.15 seconds
SIENCE! help please its due yesterday and i didn’t do it :(
Answer: H
the lights travel through the mirr to create a bigger wider light.
hope this helps (:
why does ice melt faster in water than in oil when both liquids are at the same temperature
Answer:
Because water has a high specific heat, each little bit of water flowing past can give lots of thermal energy to the ice cube. Oil has a smaller specific heat, and so more oil has to flow past to give the same amount of heat energy to the ice cube. ... Colder oil will melt ice less rapidly than warmer oil or water
what is the relationship between the perimeter and the side length of anequilateral triangle ?
Answer:
The length of the equilateral triangle's side is the length of the hypotenuse of the 30-60-90. Using this ratio, we find that the length of this triangle's hypotenuse is 4. Thus the perimeter of the equilateral triangle will be 4 multiplied by 3, which is 12.
A car on a roller coaster loaded with passengers has a mass of 2.0 x 10^3 kg. At the lowest point of the the track, the radius of curvature is 24 m and the roller coaster car has a tangential speed of 17 m/s
We have that the is mathematically given as
Fn=36000N
ForceQuestion Parameters:
mass of 2.0 x 10^3 kg
the radius of curvature is 24 m and
the roller coaster car has a tangential speed of 17 m/s
Generally the equation for the Force is mathematically given as
F=ma
Fn-fg=mv^2/r
Fn=m(v^2/r+g)
Therefore
Fn=2000(12^2/18+9.8)
Fn=36000N
For more information on Force visit
https://brainly.com/question/26115859
Why are objects that fall near Earth's surface rarely in free fall?
O Gravity does not act on objects near Earth's surface.
O Air exerts forces on falling objects near Earth's surface.
O The objects do not reach terminal velocity.
O The objects can be pushed upward by gravity.
Answer:
Air exerts forces on falling objects near earth's surface
Explanation:
Falling objects are typically subject to air resistance which prevents the force of gravity on the object
Which list of elements is placed in order from most reactive to least reactive?
A. K, Ca, Kr, Ge
B. K, Ca, Ge, Kr
C. Ca, K, Kr, Ge
D. Ge, Kr, Ca, K
Give the relationship between the number of valence electrons in an atom's
valence electron shell and the position of the element on the Periodic Table
Answer:
they're reactions
Explanation:
The relationship between the valence electrons and position is: the number of valence electrons determines the position
What is valence electron?This is the number of electrons in the outermost shell of an atom.
NOTE: The outermost shell is called valence shell
Position in Periodic tableThis is where an element is located in the periodic table
Relationship between valence electrons and positionThe position of an element in the periodic table is determined by the number of valence electrons.
For example
Sodium, Na (atomic number of 11) has the following electronic configuration
1st shell = 2 electrons2nd shell = 8 electrons 3rd (valence) shell = 1 electronSince the valence electron is 1, thus, sodium is located in group 1 of the periodic table.
Thus, we can see that the position of an element in the periodic table is related to the valence electron(s) in the atomic shell of the element.
Learn more about valence electron:
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#SPJ2
12. Which of these devices uses an electromagnet? O a light bulb O an electric motor O a refrigerator magnet a compass
Answer:
the third one with the refrigerator
5. If employers-want-union workers to return to work, they can ask the
court for an __
Answer:
they can asked to sue
Explanation:
bud
Consider the reaction below Na2CO3 (aq) + CaCl2 (aq) CaCO3 (s) + 2NaCl (aq) If the releases 39.4 kJ of energy, how many kilocalories does it release? (1 cal = 4.184 J) (Round off answer to 2 decimal place)
Answer: 9.42
Explanation: yes
A wave has a frequency of 30Hz and wave length of 40cm. What is the velocity of the wave?
Answer:
12m/s
Explanation:
v=fλ
30×(40÷100)=
12m/s
If you were to find 2 fossils, give the reasons for the way you might be able to tell which fossil is older?
Answer:
Relative Dating
Explanation:
Relative dating is used to determine a fossils approximate age by comparing it to similar rocks and fossils of known ages. Absolute dating is used to determine a precise age of a fossil by using radiometric dating to measure the decay of isotopes, either within the fossil or more often the rocks associated with it.
What is it called when a Rock forms due to heat and pressure in the earth?
Calculate the net force for each of the following:
a.
20 N to the right and 30 N to the right:
Answer and Explanation:
A.
There would be a net force of 50 N going to the right.
Since both forces are going right, they add onto the force amount.
#teamtrees #PAW (Plant And Water)
explain why when water is poured on a dry class slab it spreads uniformly but it forms spherical droplets on a waxed glass slab
Answer and Explanation:
The texture of the slabs affects the type of bonding the water molecules has with each other.
The dry glass slab allows the water to form cohesive bonds with each other, making the water stick to itself and not the slab, which makes it flow uniformly, or regularly.
The Waxed glass slab has a different texture that forms an adhesive-type bonding with water, making the water stick to the slab at certain parts/forming the spherical droplets.
#teamtrees #PAW (Plant And Water)
Which has the least gravitational force?
Answer: Mount Nevado Huascarán
Explanation: Mount Nevado Huascarán in Peru has the lowest gravitational acceleration, at 9.7639 m/s2, while the highest is at the surface of the Arctic Ocean, at 9.8337 m/s2
What is the equivalent resistance of the circuit?
Answer:
(B) 80 ohms
Explanation:
Since the circuit is a series connection, simply add the two resistances together to get 80 ohms.
The image below represents water's... *
Answer:
it represents the physical changes.
Explanation:
I
You and a friend are playing with a bowling ball to demonstrate some ideas of Rotational Physics. First, though, you want to calculate the Rotational Kinetic Energy of the bowling ball as it rolls down a sidewalk without slipping. This means it has both linear kinetic energy and rotational kinetic energy. A bowling ball can be modeled as a solid sphere rotating about its center. This bowling ball has a mass of 6.40 kg and a radius of 0.130 m. You'll need to look up the equation for the Moment of Inertia in your textbook. It is rotating with an angular velocity of 16.0 radians / second in the counter-clockwise (or positive) direction. You can use this to determine the linear velocity of the bowling ball (since it is rolling without slipping). What is the Total Kinetic Energy of the bowling ball
Answer:
K_{total} = 19.4 J
Explanation:
The total kinetic energy that is formed by the linear part and the rotational part is requested
[tex]K_{total} = K_{traslation} + K_{rotation}[/tex]
let's look for each energy
linear
[tex]K_{traslation}[/tex] = ½ m v²
rotation
[tex]K_{rotation}[/tex] = ½ I w²
the moment of inertia of a solid sphere is
I = 2/5 m r²
we substitute
[tex]K_{total}[/tex] = ½ mv² + ½ I w²
angular and linear velocity are related
v = w r
we substitute
K_{total} = ½ m w² r² + ½ (2/5 m r²) w²
K_{total} = m w² r² (½ + 1/5)
K_{total} = [tex]\frac{7}{10}[/tex] m w² r²
let's calculate
K_{total} = [tex]\frac{7}{10}[/tex] 6.40 16.0² 0.130²
K_{total} = 19.4 J