Answer:
F = 12 N
Explanation:
F = m × a
F = 3 × 4
F = 12 kg m/s²
F = 12 N
Skater begins to spend with arms held out at shoulder height. The skater wants to match the speed of the spin to the beat of the music. How does the skater use knowledge of the conservation of momentum to do this?
Answer:
the moment of inertia with the arms extended is Io and when the arms are lowered the moment
I₀/I > 1 ⇒ w > w₀
Explanation:
The angular momentum is conserved if the external torques in the system are zero, this is achieved because the friction with the ice is very small,
L₀ = L_f
I₀ w₀ = I w
w =[tex]\frac{I_o}{I}[/tex] w₀
where we see that the angular velocity changes according to the relation of the angular moments, if we approximate the body as a cylinder with two point charges, weight of the arms
I₀ = I_cylinder + 2 m r²
where r is the distance from the center of mass of the arms to the axis of rotation, the moment of inertia of the cylinder does not change, therefore changing the distance of the arms changes the moment of inertia.
If we say that the moment of inertia with the arms extended is Io and when the arms are lowered the moment will be
I <I₀
I₀/I > 1 ⇒ w > w₀
therefore the angular velocity (rotations) must increase
in this way the skater can adjust his spin speed to the musician.
6 kg block slides to the east across a frictionless surface with a momentum of 30 kg x meters per second strikes an object with an impulse of 10 newtons per second to the west of the block, what is the speed of the block at collission
Answer:
Explanation:
Initial momentum = 30 kg m/s .
impulse on the object = 10 N s towards west . = - 10 Ns
impulse = change in momentum
Let velocity after impulse be v
momentum after impulse = 6 v
change in momentum = 6v - 30
So
- 10 = 6v - 30
20 = 6v
v = 3.33 m /s
Since the velocity is positive , that means it is moving in the same direction as earlier .
asap please thank you!!
Answer:
Opinions of the author
Not relevant in a scientific paper :)
Unbeknownst to the students, every time the school floors are waxed, Mr. Tracy, the principal, likes to slide down the Hallway in his socks. Mr. Tracy weighs 85 kg and the coefficient of sliding friction between his socks and the floor is 0.120. What is the force of friction that opposes Mr. Tracy's motion down the hall?
Answer:
f = 99.96 N
Explanation:
Weight of Mr. Tracy, W = 85 kg
The coefficient of sliding friction between his socks and the floor is 0.12.
We need to find the force of friction that opposes Mr. Tracy's motion down the hall.
The force of friction is given by :
[tex]f=\mu mg\\\\f=0.12\times 85\times 9.8\\\\f=99.96\ N[/tex]
So, the required force of friction is 99.96 N.
state whether a speedometer reading of 45 km/h is the average or instantaneous speed of the car
what is the difference between an open and closed circuit?
(1) Explain : Market and its characteristics.
Answer:
market is a place where we sell or buy things ( goods)
it's characteristics are
buying and selling goods
perfect competitions
market doesn't refer only a fix place
How does a pizza,car, and a candle cause change? Correct Answer gets Brainliest:)
a 28 kg student stand on the surface of the Earth. What is the magnitude of the
gravitational force of the earth on the student?
Answer:
F = 274.68[N]
Explanation:
The gravitational force is equal to the weight of a body, or this case that of a person. Weight can be calculated by means of the product of mass by gravitational acceleration. In this way we have the following equation:
[tex]F=m*g[/tex]
where:
F = force or weight [N]
m = mass = 28 [kg]
g = gravity acceleration = 9.81 [m/s²]
Now replacing:
[tex]F=28*9.81\\F=274.68[N][/tex]
what is a frame of reference? how is it used to measure motion?
Answer:
When an object changes position with respect to a frame of reference, the object is in motion. Distance measures the path taken.
6. Abdul moves a magnetic toy train away from a magnet that cannot move. What happens to the
potential energy in the system of magnets during the movement?
a
The potential energy decreases because the train moves in the same direction as the
magnetic force.
b
The potential energy decreases because the train moves against the magnetic force.
С
The potential energy increases because the train moves against the magnetic force.
d
The potential energy does not change because the magnets in the system do not change.
Yeah
Answer: Potential energy increases because the train moves against the magnetic force.
Explanation:
When the magnetic toy train is moved away from a magnet that cannot move, the potential energy in the system of magnets during the movement is affected as there's an increase in the potential energy because the train moves against the magnetic force.
We should note that the potential energy simply means the energy that is stored in the magnetic toy. Since the magnetic toy has been moved away from the magnet, the likelihood of its attraction will reduce thereby there'll be a rise in the potential energy.
What is the main purpose of catabolism? to build up needed molecules in the body to produce energy for use by the body to remove built-up waste in the body.
Answer:
to produce energy for use by the body.
Explanation:
Catabolism can be defined as a metabolic process which typically involves the breaking down of complex molecules (inorganic and organic) into smaller and simpler molecules. This metabolic process (catabolism) is always accompanied with the release of energy in the form of adenosine triphosphate (ADP).
Some examples of the complex molecules broken down through catabolism are proteins, nucleic acid, polysaccharides, and lipids; which are broken into the following smaller molecules, amino acids, nucleotides, monosaccharides, and fatty acids respectively.
Hence, the main purpose of catabolism in living organisms such as humans, animals and plants is to produce energy for use by the body.
Answer:
to produce energy for use by the body
Explanation:
PLS ANSWER FAST THIS IS TIME TEST AND WILL GIVE BRANINLY!!!!
Answer using mass m= F divided by a
Also use kilograms {kg}
A tiny aeroplane accelerates at 35 m/ s2 with a force of 20 N. What is the mass of the aeroplane?
Answer:
0.57 kg
Explanation:
We are given that
Force, F=20 N
Acceleration ,a =[tex]35m/s^2[/tex]
We have to find the mass of Aero-plane.
To find the value of mass we will divide the force by acceleration.
We know that
Force, F=ma
Using the formula
[tex]20=m\times 35[/tex]
[tex]\frac{20}{35}=m[/tex]
[tex]m=0.57 kg[/tex]
Hence, the mass of the aero-plane=0.57 kg
A force of 20N acted on a ball thereby imparting an impulse of 70N's to the ball. For how long did the force act on the ball?
Answer:3.5 seconds
Explanation:
The height of a transverse waves is known as its?
Answer:
amplitude
Explanation:
wave is a called the crest, and the low point is called the trough. For longitudinal waves, the compressions and rarefactions are analogous to the crests and troughs of transverse waves. The distance between successive crests or troughs is called the wavelength. The height of a wave is the amplitude.…
What is the standard mesurement unit of force A joule B Newton C degrees D meters
Answer:
B,Newton
Explanation:
I hope it helps
A raindrop falls from a cloud 100 m above the ground. Neglect air resistance. What is
the speed of the raindrop when it hits the ground? Is this a reasonable number? Explain.
Answer:
Explanation:
Use the kinematic equation
[tex]V^2=V^2_i+2a(x_f-x_i)[/tex]
The initial velocity was given from the word "falls." Acceleration due to gravity is 9.8 m/s^2.
[tex]V^2=0^2+200(9.8)[/tex]
[tex]V=\sqrt{1960} =44.27m/s[/tex]
A raindrop falls from a cloud 100 m above the ground. Neglect air resistance. The speed of the raindrop when it hits the ground would be 44.27 meters/ second.
What is mechanical energy?The sum of all the energy in motion (total kinetic energy) and all the energy that is stored in the system (total potential energy) is known as mechanical energy.
As given in the problem A raindrop falls from a cloud 100 m above the ground. Neglect air resistance, then we have to find out the speed of the raindrop when it hits the ground,
The speed of the raindrop = √(2gh)
=√(2*9.8*100)
=44.27 meters/seconds
Thus, if a raindrop falls from a cloud 100 m above the ground. Neglect air resistance. the speed of the raindrop when it hits the ground would be 44.27 meters/ second.
Learn more about mechanical energy from here, refer to the link;
brainly.com/question/12319302
#SPJ2
Need help with physics.
Question: A 65 kg child riding a Ferris wheel has a tangential speed of 9.5 m/s. Find the magnitude of the centripetal force on the child if the distance from the child to the axis of the wheel is 20 m.
The centripetal force : F = 293.3125 N
Further explanationGiven
mass = 65 kg
v = 9.5 m/s
r = 20 m
Required
the centripetal force
Solution
Centripetal force is a force acting on objects that move in a circle in the direction toward the center of the circle
[tex]\large {\boxed {\bold {F = \frac {mv ^ 2} {R}}}[/tex]
F = centripetal force, N
m = mass, Kg
v = linear velocity, m / s
r = radius, m
Input the value :
F = 65 x 9.5² / 20
F = 293.3125 N
In a sonometer by what change in linear density of wire its velocity becomes double? Keeping tension of wire constant
Answer:
Explanation:
In a sonometer , expression for speed of wave produced can be given as follows .
v = [tex]\sqrt{\frac{T}{m} }[/tex]
v is velocity , T is tension in wire , m is density per unit length .
Here v is inversely proportional to square root of m . So if m becomes m / 4
velocity changes as follows .
velocity = [tex]\sqrt{\frac{T}{\frac{m}{4} } }[/tex]
= [tex]\sqrt{\frac{4T}{m} }[/tex]
= 2v
velocity becomes two times . Hence to make velocity two times , mass per unit length has to be changed to one fourth value , keeping tension constant .
PLEASE HELP SOMEONE ASAPAPP!P
PLS ANSWER FAST WILL GIVE BRAINLEST!!!
Calculate the missing variables using the necessary formula and rules using "FORCE"
How much force is needed to accelerate a 2000kg car by 3 m/s2?
Answer:
F = 6,000 N
Explanation:
F = m × a
F = 2,000 × 3
F = 6,000 kg m/s²
F = 6,000 N
Tina just threw a 0.15 kg ball straight up in the air. If the ball reaches
a height of 4.0 m, what is its gravitational potential energy at this
height?
A-27j
B-5.9j
C-13j
D-2.5j
Answer:
13 j
Explanation:
I took the test and got it wrong lol
All waves transmit energy. Only one type of wave does not require a medium to transmit energy. That is a _____wave?
A(compression
B(Electromagnetic
C(sound
D(water
Answer:
sound waves
Explanation:
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How would you describe impulse in the simplest way possible
Answer:
Explanation:
impulse is a sudden force or desire — this could be an electrical impulse, or an impulse to get some pizza.
If you act on a sudden feeling or thought, you’re following an impulse.
That's like a whim: an impulse isn't something you've given a lot of thought. Another meaning of impulse is an electrical charge or pulse. Electrical impulses are coursing through wires all through your house every day. Both kinds of impulses make things happen. The electrical impulse keeps the refrigerator going, and then you have an impulse to eat all the ice cream in the fridge.
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compare the physical properties of air and gold .
Answer:
Gold is metallic, with a yellow color when in a mass, but when finely divided it may be black, ruby, or purple. It is the most malleable and ductile metal; 1 ounce (28 g) of gold can be beaten out to 300 square feet. It is a soft metal and is usually alloyed to give it more strength.
Formula --
Molecular Weight (lb/m o l) 28.96
Critical Temp. (°F) N/A
Critical Pressure (p s i a) N/A
Boiling Point (°F) -317.8
Melting Point (°F) N/A
Psat 70°F (p s i a) (note 1)
Explanation:
I can't wait till Christmas!!!
Answer:
Good for you!
Cual es el volumen en m³ y en litros de 3000N de aceite de oliva cuyo peso espesifico es de 9016 N/M³
Answer: I am sorry but I don't know what you're trying to say.
Explanation: Hope
A beaker containing ice and water is placed on a warm hotplate. What type of change would you expect
the ice to undergo
Answer:
Solid to liquid
Explanation:
Ice cubes are solid, adding heat to the beaker will melt the ice cubes to water.
The amount of blank
that occurs when a sound wave encounters a
barrier depends on the wave's wavelength.
Answer:
where is the paragraph so i can read
Answer:
Diffraction
Explanation:
Look at the definition of Diffraction in your notes and quiz just taken
Select all that apply. According to scientists, the distribution of volcanoes throughout the world…
Forms a specific pattern across fault lines
Corresponds to plate boundaries
Is constantly changing and shifting
Is fairly even and widespread
Answer:
Corresponds to plate boundaries
Is constantly changing and shifting
Explanation: