Two forces act in opposite directions on a wood block. What will happen if the forces are unbalanced?
A. The block will balance the forces.
B. The forces will reverse direction.
C. The mass of the block will change.
D. The position of the block will change.
Answer:
D
Explanation:
If two unequal forces act in opposite directions, one larger force must cancel out the smaller force,
leaving the net force to be some number in one direction.
Take for example a game of tug-of-war; there are two OPPOSITE forces (groups of people) acting on the rope, one force is pulling with a force in the negative direction while the other force is pulling in the positive direction.
If the forces on the rope were unequal, then the stronger force (group) will pull everything in their direction.
The same will happen on two unequal forces of opposite directions acting on a wooden block. Therefore, since the resultant force will have a non-zero magnitude and direction, there will be a change in the block's motion and position.
A3.0 105 kg freight car moving at 2.5 m/s east, strikes a
stationary 1.5 x 105 kg car. If the two cars end up connected
to each other, what is their resulting velocity?
Answer:3.4 miles west
Explanation:
You walk exactly 250 steps North, turn around, and then walk exactly 400 steps South. How far are you from your starting
point?
steps to the
North, South, East or West)
Answer:
150 steps south
Explanation:
250 north 250 back to start then continue south for remainder of 400 steps. 150 south
A communication satellite is in a circular path orbit around Earth. If the speed of the satellite is constant, the net force acting on the satellite ____.
Answer:
is changing in direction, but constant in magnitude
Explanation:
This question is a bit tricky since the velocity of the satellite is changing, but the speed is constant.
Speed is simply a measure of how fast you are going. It doesn't matter where you're going, just how quickly.
Velocity, on the other hand, does care about which direction you're going. For example, it could be then when you travel right, your velocity is positive, and when you travel left, your velocity is negative. This is the similar for a 2D shape like a circular orbit
Since we know velocity is changing, there must be acceleration which changes that velocity (since acceleration is the change in velocity: going from 0 to 60 mph, for example)
Thus, with a non-zero net acceleration, we know that there must be a force that is changing in direction, but constant in magnitude (since the orbit is a circle, and always attracted to the center of the Earth at equal distance).
what is the speed of a 330kg beam dropped from 40m
Answer:
28 m/s
Explanation:
We can use this constant acceleration kinematic equation to find the speed of this beam as it is dropped from 40 m.
Since the object is dropped vertically downwards, we know that the object is in free-fall.
The acceleration of this object is -g, which is -9.8 m/s² since we are making the positive direction upwards and the negative direction downwards.
The initial velocity is 0 m/s since the object is dropped and starts from rest.
The final velocity is what we are trying to solve for.
The displacement in the y-direction is 40 m.
Now we can see which equation contains these 4 variables:
v² = v₀² + 2aΔxPlug in the known variables.
v² = (0)² + 2(-9.8)(-40)Simplify this equation.
v² = 784Take the square root of both sides.
v = 28 m/sThe speed of the 330 kg beam dropped from 40 m is 28 m/s.
Answer:
28 m/sExplanation:
Given information :
mass = 330kg
height =40m
v = √2gh
Where ;
g = acceleration due to gravity = 9.8 or 10 m/s
h = height
how much total energy of the beam just as it hits the ground =
mgh
[tex]330\times 10\times 40\\\\\\=132000[/tex]
Speed at which the beam will hit the ground :
[tex]v = \sqrt{2\times 10\times40} \\\\=\sqrt{800}\\\\=20\sqrt{2}\\\\v=28.28427[/tex]
1. What is the speed of a runner who runs 400 meters in 40
seconds?
Answer:
10 m/s
Explanation:
Speed = Distance / Time
Speed = 400 / 40
Speed = 10
Unit = meters per second = m/s
Write true if the statement is correct and false if the statement
1. Magnetic poles always appear in pair.
2. Iron and nickel are examples of magnetic materials.
3. The two ends of a magnet are called magnetic poles.
4. Two similar magnetic poles attract each other
5. If one end of an iron bar attracts one pole of a com
Grade 7 Physics
then the iron bar must be a magnet.
Match the terms in column A with the phrases in colu
B
Answer:
true false
Explanation:
Answer:
1.true
2.true
3.true 4.false 5.true
(b) () State what is meant by specific acoustic impedance.
...........[2]
Answer:
.
Explanation:
.
The density of a substance is 3.4 g cm-3. Its relative density relative to another substance is 2.0. what is the density of the second substance?
Answer:
1.7 g/cm³
Explanation:
Given that:
Density of substance = 3.4 g/cm³
Relative density to another substance = 2
Density of second substance=?
Let density of second substance = x
Relative density = density of substance / density of second substance
Relative density = density of substance / x
2.0 = 3.4g/cm³ / x
2 * x = 3.4 g /cm³
x = 3.4 g/cm³ ÷ 2
x = 1.7 g/cm³
If an object has a weight of 4050 N near the surface of the Earth, what is its mass?
Answer:
417.5 kg
Explanation:
Since the gravitational for of attraction F, equals the weight of the object W when its close to the earth, F = GMm/R² = W = mg where m = mass of object and g = acceleration due to gravity close to the earth = 9.8 m/s².
g = GM/R² where g = acceleration due to gravity close to the earth, G = universal gravitational constant = 6.67 × 10⁻¹¹ Nm²/kg², M = mass of earth = 5.927 × 10²⁴ kg and R = radius of earth = 6.4 × 10⁶ m
So, g = GM/R²
= 6.67 × 10⁻¹¹ Nm²/kg² × 5.927 × 10²⁴ kg/(6.4 × 10⁶ m)²
= 39.53 × 10¹³ Nm²/kg ÷ 40.96 × 10¹² m²
= 9.65 N/kg
≅ 9.7 N/kg
= 9.7 m/s²
Since W = 4050 N and W = mg
m = W/g = 4050 N/9.7 m/s²
= 417.53 kg
≅ 417.5 kg
So, the mass of the object is 417.5 kg
How much heat is lost by 2.0 grams of water if the temperature drops from 31 °C to 29 °C? The specific heat of water is 4.184 J/(g • °C) *
1 point
a) 4.0 J
b) - 7.5 J
c)- 8.4 J
d) - 16.7 J
Given :
Mass of water, m = 2 grams.
The temperature of water drops from 31 °C to 29 °C .
The specific heat of water is 4.184 J/(g • °C).
To Find :
Amount of heat lost in this process.
Solution :
We know, heat lost is given by :
[tex]Heat\ lost,H = ms( T_f - T_i)\\\\H = 2\times 4.184 \times ( 31 - 29 )\ J\\\\H = 16.736\ J[/tex]
Therefore, amount of heat lost in this process is 16.736 J.
Calculate the gravitational force between a 4.0 x 10^8 kg mass and a 2.8 x 10^5 kg mass separated by a distance of 1.0 x 10^4 m.
Answer:
[tex]F_{g}=7.4704\times10^{-5}[/tex]
Explanation:
Givens: d = 1.0 × [tex]10^{4}[/tex] [tex]m_{1} = 4.0 x 10^{8}[/tex] [tex]m_{2} = 2.8[/tex]×[tex]10^{5}[/tex]
Required: [tex]F_{g}=?[/tex]
Formula: [tex]F_{g}= \frac{(6.67x10^{-11})(m_{1})(m_{2}) }{d^{2}}[/tex] (6.67x10^-11 is the gravitational constant)
[tex]F_{g}=\frac{\left(6.67\cdot10^{-11}\right)\left(4.0\cdot10^{8}\right)\left(2.8\cdot10^{5}\right)}{\left(1.0\cdot10^{4}\right)^{2}}[/tex]
[tex]F_{g}=7.4704\times10^{-5}[/tex]
Ramas weight is 40 kg. She is carrying a load of 20 kg up to a height of 20 m. What work does she do? What work does she do?
Answer:
The work done by Ramas is 3920 N.
Explanation:
Given;
mass of the load lifted by Ramas, m = 20 kg
height through which the load is lifted, h = 20 m
The work done by Ramas is equal to gravitational potential due to the height in which the load is lifted.
W = PE = mgh
where;
g is acceleration due to gravity = 9.8 m/s²
W = 20 x 9.8 x 20
W = 3920 N.
Therefore, the work done by Ramas is 3920 N.
A string of length 0.67 m and mass 2.0 g is held at both ends under tension. The string
produces a 700 Hz tone when it vibrates in the fourth harmonic. During this event, what is the
wavelength of the standing wave in the string?
.34
.55
.61
.45
.49
Answer:
The value is [tex]\lambda = 0.335 \ m[/tex]
Explanation:
From the question we are told that
The length of the string is [tex]l = 0.67 \ m[/tex]
The mass is [tex]m = 2.0 \ g = 0.002 \ kg[/tex]
The frequency produced at fourth harmonic vibration(i.e n =4 ) is [tex]f = 700 \ Hz[/tex]
Generally the wavelength of the string is mathematically represented as
[tex]\lambda = \frac{ 2L }{n }[/tex]
=> [tex]\lambda = \frac{ 2 * 0.67 }{ 4 }[/tex]
=> [tex]\lambda = 0.335 \ m[/tex]
Solve ASAP please!!!
Which of these best describes science?
A-Science is the study of fundamental problems such as existence, values, and reason.
B-Science is the collection of all living things on Earth.
C-Science is a body of knowledge and a process of discovery that allows people to understand the natural
world.
D-Science is the practice of diagnosing, treating, and preventing disease.
please answer it fast and correctly
Answer:
(1) chess is played by him
(2) The great black engine was seen by her
(3) Arrangements for functions had been made by him
(4) A meeting is being attended by Raman
= when the last of the guests left, I went back into the hall to look for my mobile phone that I had kept on the table, I found that my mobile phone was not there. I felt freaked and I asked to every member of my family about my phone, but nobody had idea about that. then there was a phone call made by my uncle to my father, that his son had taken the mobile by mistake. After sometime, My uncle came to return my mobile. Then I took a sigh of relief .
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What is an astronomical unit or AU
Answer:
D
Explanation:
Answer:
Astronomical Unit = 4.8481×10−6 pc; 1.5813×1.
Or even AU = Equal to
Explanation:
A 100 kg skateboarder sits at the top of a 10 m halfpipe, ready to go down the ramp. What will be his velocity when
he is 4 m off of the ground?
Answer:
v = 10.85 m/s
Explanation:
We will apply the law of conservation of energy to the skateboarder. Neglecting the frictional effects, the law of conservation of energy can be written as:
[tex]Loss\ in\ Potential\ Energy\ of\ Skateboarder = Gain\ in\ Kinetic\ Energy\ of\ Skateboarder[/tex][tex]mg\Delta h = \frac{1}{2}mv^2\\\\v^2 = 2g\Delta h\\v = \sqrt{2g\Delta h} \\[/tex]
where,
v = velocity of skateboarder = ?
g = acceleration due to gravity = 9.81 m/s²
Δh = change in height = 10 m - 4 m = 6 m
Therefore,
[tex]v = \sqrt{{(2)(9.81\ m/s^2})({6\ m})}}[/tex]
v = 10.85 m/s
What is the mathematical relationship between wavelength and velocity? PLZ HELP MEEE
Answer: wavelength is the length of the wave, example the length of a sound wave.
Velocity is also known as speed.
Explanation:
A woman has a mass of 55 kg on earth. what would be the women's weight on the moon? (The moon’s gravity is 1.6 N).
Answer:
i dont know the answer sorry have a good day
Explanation:
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difference between lower fixed point and upper fixed point
Answer:
The lower fixed point, or ice point, is the temperature of pure melting ice at normal atmospheric pressure. The upper fixed point, or steam point, is the temperature of pure boiling water at normal atmospheric pressure.
Explanation:
A Force is applied onto a mass causing it to accelerate. If the same Force was applied to a SMALLER mass, what would happen to that acceleration?
1. The acceleration would increase
2. The acceleration would stay the same
3. The acceleration would decrease
4. The acceleration would change direction
Answer:
1. The acceleration would increase.
Explanation:
This is because according to Newton's law, the less mass there is, the more velocity.
According to newton's second law, if you have an object that is put under acceleration due to a force, how could you reduce the acceleration
Answer:
We could reduce the force or increase the mass of the object.
Explanation:
Using the definition of force, according to Newton's second law, (F = ma) the acceleration is directly proportional to the force and inversely proportional to the mass. Therefore, if we want to reduce the acceleration of an object we have two options:
We could reduce the force We could increase the massIn both cases a will decrease.
I hope it helps you!
HELP PLEASE URGENT
If a 0.16 kg 8-ball at rest is hit by the 0.17 kg cue ball that is moving at a speed of 2 m/s, what is the speed of the 8-ball if the cue ball is completely stopped after the collision?
Answer:
The speed of the 8-ball is 2.125 m/s after the collision.
Explanation:
Law Of Conservation Of Linear Momentum
The total momentum of a system of masses is conserved unless an external force is applied. The formula for the momentum of a body with mass m and velocity v is
P=mv
If we have a system of masses, then the total momentum is the sum of them all
[tex]P=m_1v_1+m_2v_2+...+m_nv_n[/tex]
If a collision occurs, the velocities change to v' and the final momentum is:
[tex]P'=m_1v'_1+m_2v'_2+...+m_nv'_n[/tex]
In a system of two masses, the law of conservation of linear momentum takes the form:
[tex]m_1v_1+m_2v_2=m_1v'_1+m_2v'_2[/tex]
The m1=0.16 Kg 8-ball is initially at rest v1=0. It is hit by an m2=0.17 Kg cue ball that was moving at v2=2 m/s.
After the collision, the cue ball remains at rest v2'=0. It's required to find the final speed v1' after the collision.
The last equation is solved for v1':
[tex]\displaystyle v'_1=\frac{m_1v_1+m_2v_2-m_2v'_2}{m_1}[/tex]
[tex]\displaystyle v'_1=\frac{0.16*0+0.17*2-0.17*0}{0.16}[/tex]
[tex]\displaystyle v'_1=\frac{0.34}{0.16}[/tex]
[tex]v'_1=2.125\ m/s[/tex]
The speed of the 8-ball is 2.125 m/s after the collision.
De-Broglie postulated that the relationship, lambda=h/p is valid for relativistic particles. Find out the de-Broglie wavelength for an electron whose kinetic energy is 3MeV.
Given :
An electron with kinetic energy of 3 MeV.
To Find :
The de-Broglie wavelength for that electron.
Solution :
We know, de-Broglie wavelength for an electron with kinetic energy K.E is given by :
[tex]\lambda = \dfrac{h}{\sqrt{2m(K.E)}}[/tex]
Putting all given values in above equation, we get :
[tex]\lambda = \dfrac{6.626\times 10^{-34}}{\sqrt{2\times 9.1\times 10^{-31}\times 3\times 10^6 \times 1.6\times 10^{-19}}}\\\\\\\lambda = 7.089 \times 10^{-13} \ m[/tex]
Hence, this is the required solution.
Place the molecules in the list in order with the smallest molecules at the top and largest molecules at the bottom: starch molecule, water molecule, glucose molecule, carbon dioxide molecule, protein molecule, amino acid molecule, oxygen molecule
Explanation:
list in order with the smallest molecules at the top and largest molecules at the bottom:
1.Oxygen
2.Water
3.Carbon dioxide
4.amino acid
5.Glucose
6. Starch
7. Protein
The molecules can be arranged as follows with the smallest at the top is oxygen, water, carbon dioxide, amino acid, glucose, starch, protein.
The given molecules;
starch, water, glucose, carbon dioxide, protein, amino acid, oxygen
The molecular weight of the given compounds is listed as follows;
water -------- 18 g/mol
glucose ------- 180.2 g/mol
starch (2 or more glucose) ------ 360 g/mol
carbon dioxide ------ 44 g/mol
protein -------- 20,000 g/mol
amino acid (glycine) ----- 75 g/mol
oxygen -------- 16 g/mol
Thus, the molecules can be arranged as follows with the smallest at the top;
oxygenwatercarbon dioxideamino acidglucosestarchproteinLearn more here:https://brainly.com/question/19537339
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A 2.0 kg bullet is fired into a sandbag sitting on a wagon. The combined mass of the wagon and the sandbag is 4.5 kg. a) If the wagon/sandbag/bullet moved together with a speed of 0.22 m/s immediately after impact with the bullet, with what speed did the bullet enter the sandbag? b) Is this an elastic or inelastic collision? Explain.
Answer:
To answer your question use the code ICE on here to get your answer works every time for me hope this helps
what happens when heat is removed from water? the water particles move farther apart. the water changes from a liquid to a gas. the temperature of the water increases. the kinetic energy of the water particles decreases.
Answer:d
Explanation:
Which of the following are single-displacement reactions?
A Mg (s) + 2H,0 (g) → Mg(OH)2 (aq) + Hz (g)
B. 2C,H6 (g) + 70, (g) → 6H,0 (9) + 4CO, (g)
c. AgNO3 (aq) + NaCl (aq) → AgCl (s) + NaN3 (aq)
D. Clz (9) + KBr (aq) → KCI (aq) + Br2 ()
Multiple answer are allowed!!!
Answer:
A & D
Explanation:
A single-displacement reaction is a chemical reaction whereby one element is substituted for another one in a compound and thereby generating a new element and also a new compound as products.
From the options, only options A & D fits this definition of single-displacement reactions.
For option D: Both left and hand and right hand sides each have one element and one compound. We can see that K is substituted from KBr to join Cl to form KCl and Br2 on the right hand side.
For option A: Both left and hand and right hand sides each have one element and one compound. We can see that OH is substituted from 2H2O to join Mg to form Mg(OH)2 and H2 on the right hand side.
The other options are not correct because they don't involve only and element and a compound on each side of the reaction.
In an A.C circuit current leads voltage by phase π/2 then circuit is
Answer:
capacitive
Explanation:
In a capacitive circuit, current is proportional to the derivative of the voltage. For a sinusoidal excitation, this means current is at the highest level when voltage is increasing through zero. That is, current leads the voltage.