Answers
Spring Balance= Measures the force acting on an object
Bird=Drag
Reduces Friction=Static Friction
Related Questions
A brass rod and an iron rod differ in length by 28cm at 20°C. What should be the original length of the iron rod for the difference in length to remain the same when both rods are heated to 90°C? Linear expansivity of brass=1.9×10^-5. Linear expansivity of iron=1.2×10^-5.
Pls show workings.
Answers
Answer:
The original length of the iron rod is approximately 572.189 meters.
Explanation:
This is a case of linear expansion, which is defined by the following differential equation:
[tex]\alpha = \frac{1}{L}\cdot \frac{dL}{dT}[/tex] (1)
Where:
[tex]\alpha[/tex] - Linear expansion coefficient, measured in [tex]\frac{1}{^{\circ}C}[/tex].
[tex]L[/tex] - Length of the element, measured in centimeters.
[tex]\frac{dL}{dT}[/tex] - First derivative of the length of the element with respect to temperature, measured in centimeters per degree Celsius.
If we assume that thermal deformation are small regarding the length of the element, then we simplify (1) in the following form:
[tex]\alpha \approx \frac{\Delta L_{o}}{L\cdot \Delta T}[/tex]
[tex]L_{f} -L_{o} = \alpha \cdot L_{o} \cdot \Delta T[/tex]
[tex]L_{f} = L_{o}\cdot [1+\alpha\cdot (T_{f}-T_{o})][/tex] (2)
Where:
[tex]L_{o}[/tex], [tex]L_{f}[/tex] - Initial and final lengths of the element, measured in centimeters.
[tex]T_{o}, T_{f}[/tex] - Initial and final temperatures of the element, measured in degrees Celsius.
Given that brass has a higher coefficient of linear expansion, it is suppose that initial length is less than the initial length of the iron element. Then, we have the following system of linear equations:
Brass
[tex]L = L_{o}\cdot [1+\alpha_{B}\cdot (T_{f}-T_{o})][/tex] (3)
Iron
[tex]L = (L_{o}+28)\cdot [1+\alpha_{I}\cdot (T_{f}-T_{o})][/tex] (4)
Where [tex]\alpha_{B}[/tex], [tex]\alpha_{I}[/tex] are coefficients of linear expansion of brass and iron, measured in [tex]\frac{1}{^{\circ}C}[/tex].
By equalizing (3) and (4), we have the following formula:
[tex]L_{o} \cdot [1+\alpha_{B}\cdot (T_{f}-T_{o})] = (L_{o}+28)\cdot [1+\alpha_{I}\cdot (T_{f}-T_{o})][/tex]
[tex]L_{o} \cdot (\alpha_{B}-\alpha_{I})\cdot (T_{f}-T_{o}) = 28\cdot [1+\alpha_{I}\cdot (T_{f}-T_{o})][/tex]
[tex]L_{o} = \frac{28\cdot [1+\alpha_{I}\cdot (T_{f}-T_{o})]}{(\alpha_{B}-\alpha_{I})\cdot (T_{f}-T_{o} )}[/tex]
If we know that [tex]\alpha_{B} = 1.9\times 10^{-5}\,\frac{1}{^{\circ}C}[/tex], [tex]\alpha_{I} = 1.2\times 10^{-5}\,\frac{1}{^{\circ}C}[/tex], [tex]T_{o} = 20\,^{\circ}C[/tex] and [tex]T_{f} = 90\,^{\circ}C[/tex], then the initial length of the iron rod is:
[tex]L_{o} = \frac{28\cdot [1+\left(1.2\times 10^{-5}\,\frac{1}{^{\circ}C} \right)\cdot (90\,^{\circ}C-20\,^{\circ}C)]}{\left(1.9\times 10^{-5}\,\frac{1}{^{\circ}C}-1.2\times 10^{-5}\,\frac{1}{^{\circ}C} \right)\cdot (90\,^{\circ}C-20\,^{\circ}C)}[/tex]
[tex]L_{o} = 57190.857\,cm[/tex]
[tex]L_{o, I} = 57218.857\,cm[/tex]
[tex]L_{o,I} = 572.189\,m[/tex]
The original length of the iron rod is approximately 572.189 meters.
How many sig figs are in 0.32
Answers
Scott needs to split a chunk of wood for the fire. There is a crack in the chunk. If he uses an axe it will use 200 Joules of energy. He receives 100 Joules of work out of the machine.
A) What type of simple machine has he used?
B) What is the efficiency of the machine?
Answers
Answer:
A) A wedge
B) The efficiency of the machine is 50%
Explanation:
The type of simple machine Scott used is the wedge
A) A wedge is a simple machine that consists of a long thick metal or wood stem that tapers to a thin (Relatively sharp) end. It is used for a splitting, tightening, and lifting.
An example of a wedge is an axe
B) The efficiency of a machine is given approximately as the ratio of the work output to the work input as follows;
The amount of input energy the axe uses = 200 Joules
The amount of output work Scott receives from the axe = 100 Joules
Therefore, the efficiency of the machine, η, is given as follows;
[tex]\eta = \dfrac{The \ out.put \ work \ Scott \ receives \ from \ the \ axe}{The \ amount \ of \ in.put \ energy \ the \ axe \ uses} \times 100[/tex]
[tex]\therefore \eta = = \dfrac{100 \ J}{200 \ J} \times 100 = 50\%[/tex]
The efficiency of the machine, η = 50%
3 ways that asteroids are like planets
Answers
Answer:
1.Asteroids aren't all round like planets. They have jagged and irregular shapes.
2.Some asteroids are hundreds of miles in diameter, but many more are as small as pebbles.
3.Most asteroids are made of different kinds of rocks, but some have clays or metals, such as nickel and iron.
Explanation:
it is simple really u just need to remember that astorids do not orbit a sun they crash into things like planets and mess them up really bad if they hit our sun which might happen it will just burn up because our sun is so hot that it can burn stuff if a astorid hits earth it wont be to bad for our earth at all it might cause some damage but we will be fine.
Does your shadow grow bigger when the sun is in front of you or behind you
Answers
Answer:
behind
Explanation:
because just because that's why lol
A bowling ball rolls off a cliff at 5 m/s. The vertical velocity after 1 second is.....
A. 9.8 m/s
B. 19.6 m/s
C. 29.4 m/s
Answers
Answer:
A. 9.8 m/s
Explanation:
The vertical velocity of an object increases by 9.8 m/s each second. After 1 second, the bowling ball would have a vertical velocity of 9.8 m/s.
A box of mass m is held at rest on a frictionless surface with force F up the ramp. The ramp has an angle
What is the magnitude of the normal force?
Choose 1 answer:
Answers
The magnitude of the normal force is to be considered as the mg cos θ when the box of mass m is at rest.
What is magnitude?In terms of physics, it refer to the maximum size where it should be extended also it defined the object direction. It is factor for vector and the scalar quantities.
When the box of mass m should be at rest so here the ramp should be an angle so here the weight should be perpendicular to the string.
hence, The magnitude of the normal force is to be considered as the mg cos θ when the box of mass m is at rest.
Learn more about magnitude here: https://brainly.com/question/14576767
a concave mirror of radius of curvature 20cm produces an inverted image three times the size of an object placed on and perpendicular to the axis. calculate the position of the object and the image
Answers
Answer:
Check attachment for your answer
Good luck
what law of motion does this picture represent?
Answers
How will the electrostatic force be changed if the distance between electric charges is reduced one half of the original distance?
A) more than original force
B) less than original force
C) impossible to determine
D) the same as original force
Answers
The unit for mass is grams. The units for molar mass is g/mol? True or false
Answers
Answer:
2.False 1.False.
Explanation:
2. I think Because it's formula is kilogram/mole
1 The si unit of mass is KG.
POSS An apple with a mass of 2 kg falls from a tree with an acceleration of 9 "What is the net force of the apple as it hits the ground?
Answers
Answer:
F = 19.62[N]
Explanation:
By means of Newton's second law which tells us that the sum of the forces on a body is equal to the product of mass by acceleration, we can determine the force.
[tex]F=m*a[/tex]
where:
F = force [N]
m = mass = 2 [kg]
a = gravity acceleration = 9.81 [m/s²]
Now replacing:
[tex]F=2*9.81\\F=19.62[N][/tex]
Mr. Covault gave his students an assignment to design and conduct experiments that would allow them to find the relationship between force, mass, and acceleration. Some students decided to use a setup like the one below:
The applied force in this setup is equal to the weight of the item attached to the end of the pulley. One student tested the acceleration due to this force on a wooden block (as shown above); another student used a wheeled cart instead of a wooden block.
Mr. Covault's other students decided to simply drop objects. The force in that case is the weight of the object.
All the students measured the time it took each object, starting from rest, to move a certain distance. They used the time and distance to calculate the average acceleration.
Four students' results are shown below. A successful experiment should eliminate all forces acting on the object except the force being investigated. The experiment should confirm Newton's second law:
One newton (N) is 1 kg·m/s2.
Which of the following students had a well designed and conducted experiment?
Student Mass
(kg) Force
(N) Measured
Acceleration
(m/s2)
Kira 0.21 0.098 0.0047
Sophie 0.11 0.098 0.88
Jacques 0.050 0.49 4.9
Chase 0.50 4.9 8.9
Answers
Answer:
Sophie
Explanation:
Only Sophie's results supported Newton's second law. The other students' measured accelerations were significantly lower than expected. This could indicate that their experimental designs had not sufficiently eliminated drag forces.
F=ma Rearranging when solving for acceleration gives: a=F/m
What is the medium when you are in your bedroom listening to the radio?
Answers
Answer:
this equation doesn't work
Explanation:
no one listens to radio anymore
Answer:
What numbers?
Explanation:
What happens to the gravitational force between two objects when the distance between them is reduced by 50%?
A the gravitational force decreases by 50%
B the gravitational force increases by 50%
Cthe gravitational force decreases by 25%
the gravitational force increases by 400%
Question 8
Answers
Answer:
B
Explanation:
If you ride your bike at an average speed of 5 km/h and need to travel a total distance of 35 km, how long will it take you to reach your destination?
Answers
Answer:
7 hours.
Explanation:
This is because you are traveling 5 kilometers per hour so 5 multiplied by 7= 35.
Which wave, A or B, has higher energy?
A
O A, because it has a higher amplitude
OB, because it has a higher amplitude
O A, because it has a lower amplitude
OB, because it has a lower amplitude
АЛЛА
B
Answers
Answer:
Wave A.
Explanation:
The energy of a wave is directly proportional to the square of the amplitude.
If a wave has higher amplitude, it will have more energy. On the other hand, a wave having lower amplitude, it will have less eenergy.
In this case, we need to tell which wave has higher energy. Hence, the correct option is A because it has a higher amplitude.
Calculate the velocity of the objects motion represented in the following graph. Show all your work.
Pleaseeeee?????? I need help!!!!!!!!
Answers
as we know that velocity= displacement/change in time
hence velocity here is= 11-3/12-0
=8/12
=2/3
=0.667m/s
hopefully i am right
9.In a perfectly elastic collision, a 0.400 kg ball moving toward the east at 3.7 m/s suddenly
collides head-on with a 0.200 kg ball sitting at rest.
If the velocity of the first ball just after the collision is 4.24 m/s, what is the velocity of the second ball ?
Answers
Answer:
The velocity of the second ball is 15.88 m/s East
Explanation:
The given parameters are;
The type of collision = Perfectly elastic collision
The mass of the ball moving East, m₁ = 0.400 kg
The velocity of the ball moving East, v₁ = 3.7 m/s
The mass of the ball at rest, m₂ = 0.200 kg
The initial velocity of the ball at rest, v₂ = 0 m/s
The velocity of the first ball, 'm₁', after the collision, v₃ = 4.24 m/s (The direction is assumed as being towards the West)
The velocity, 'v₄', of the second ball, 'm₂', after the collision is given by the law of conservation of linear momentum as follows;
m₁·v₁ + m₂·v₂ = m₁·v₃ + m₂·v₄
Substituting the known values gives;
0.400 kg × 3.7 m/s + 0.200 kg × 0 m/s = 0.400 kg × (-4.24 m/s) + 0.200 kg × v₄
∴ 0.200 kg × v₄ = 0.400 kg × 3.7 m/s - 0.400 kg × (-4.24 m/s)
Therefore;
0.200 kg × v₄ = 0.400 kg × 3.7 m/s + 0.400 kg × 4.24 m/s = 3.176 kg·m/s
v₄ = 3.176 kg·m/s/(0.200 kg) = 15.88 m/s
The velocity of the second ball = v₄ = 15.88 m/s East.
Which has more kinetic energy, a 4.0 kg bowling ball moving at 1.0 m/s or a 1.0 kg
bocce ball moving at 4.0 m/s? Explain your answer
Answers
Answer:
The kinetic energy of bocce ball is more.
Explanation:
Given that,
Mass of a bowling ball, m₁ = 4 kg
Speed of the bowling ball, v₁ = 1 m/s
Mass of bocce ball, m₂ = 1 kg
Speed of bocce ball, v₂ = 4 m/s
We need to say which has more kinetic energy.
The kinetic energy of an object is given by :
[tex]E=\dfrac{1}{2}mv^2[/tex]
Kinetic energy of the bowling ball,
[tex]E_1=\dfrac{1}{2}m_1v_1^2\\\\E_1=\dfrac{1}{2}\times 4\times (1)^2\\\\E_1=2\ J[/tex]
The kinetic energy of the bocce ball,
[tex]E_2=\dfrac{1}{2}m_2v_2^2\\\\E_2=\dfrac{1}{2}\times 1\times (4)^2\\\\E_2=8\ J[/tex]
So, the kinetic energy of bocce ball is more than that of bowling ball.
What factor from the choices below determines whether
a star will evolve into a white dwarf, a neutron star, or a
black hole?
A) mass
B) percentage of helium
C) percentage of carbon
D) apparent brightness
Answers
Answer:
a
Explanation:
Stars with very big masses will become neutron stars or black holes.
Smaller stars will become white dwarfs
A flashlight is shone on a mirror. As you move the flashlight to increase the angle of incidence of the light on the mirror, the angle of the reflection also changes. How does the angle of reflection change?
Answers
Answer:
the angle of reflection also increases
Explanation:
this is because the law of reflection states that the angle of incidence equals to the angle of reflection, thus, if the angle of incidence increases, angle of reflection should also increase, basically , think as if the angle of incidence is the same thing as the angle of reflection
hope this helps, if not please report it someone else can try it
A machine with a velocity ratio moves a load of 3000N when an effort of 200N is applied. Calculate the efficiency energy
Answers
Explanation:
A machine with a velocity ratio of 30 moves a load of 3000N when an effort of 200N is applied.the efficiency of the machine is what?
A car starts from rest and after 20 seconds it's velocity becomes 108km find the acceleration of the car
Answers
Answer:
1.5 km/s²
Explanation:
Given that:
a car starts from rest; it means the initial velocity (u) = 0 km/hr = 0 m/s
after time (t) = 20 seconds
the final velocity = 108 km/hr = 30 m/s
The acceleration (a) of the car can be determined by using the formula:
[tex]a = \dfrac{v-u}{t}[/tex]
[tex]a = \dfrac{30\ m/s -0 \ m/s}{20 \ s}[/tex]
[tex]a = \dfrac{30 \ m/s}{20 \ s}[/tex]
a = 1.5 km/s²
Radars can help meteorologists detect clouds and sailors detect submarines. Radars send out radio waves and record their echoes after the radio waves reflect off an object. Two radars send out radio waves with the same frequency. The first radar sends radio waves through the air. The second radar sends radio waves through the ocean. What is true about these radio waves? SC.7.P.10.3 A. They are visible. B. They are audible. C. They have different speeds D. They have the same wavelength
Answers
Answer:
They have different speeds
Explanation:
Answer:
They have different speeds
Explanation:
A projectile is fired at an angle of 53° to the horizontal with a speed of 80. meters per second. What is the vertical component of the projectile's initial velocity?
A) 100 m/s B) 64 m/s C) 48 m/s D) 130 m/s
Answers
Answer:64 m/s
Explanation:❤️
A simple pendulum takes 128s to complete 40 oscillations what is the time period of the pendulum
Answers
Explanation:
Parameters
Number of oscillation = 40 oscillations
Time of oscillation = 128s
Formular
Period (T) = No of oscillation
Time taken
T = 128
40
T=3.2s
Define 1 watt power?
Answers
Answer:
A body is said to have power of 1 watt if it does work at the rate of 1 joule in 1 s. Watt is the SI unit of power. Other units of power include ergs per second, horsepower, metric horsepower or cheval vapeur (CV)), and foot-pounds per minute. The unit Watt is named after the scientist James Watt.
1. How do humans get energy from food?
Answers
Answer: small intestine
Explanation:
I took a test
A force of 5.0 moves a 6.0 kg object along a rough floor at a constant speed of 2.5 m/s. What power is being used? What force of friction is acting on the object?
Answers
Complete Question:
A force of 5.0 N moves a 6.0 kg object along a rough floor at a constant speed of 2.5 m/s.
(a) How much work is done in 25 s?
(b) What power is being used?
(c) What force of friction is acting on the object?
Answer:
a. Workdone = 312.5 Joules.
b. Power = 12.5 Watts.
c. Force of friction = 5 Newton.
Explanation:
Given the following data;
Force = 5N
Speed = 2.5m/s
Mass = 6kg
Time = 25 secs
a. To find the work done.
We would first solve for the distance covered by the object.
Distance = speed * time
Distance = 2.5 * 25
Distance = 62.5 meters.
Workdone = force * distance
Workdone = 5 * 62.5
Workdone = 312.5 Joules.
b. To find the amount of power being used.
Power = workdone/time
Power = 312.5/25
Power = 12.5 Watts.
c. To find the force of friction is acting on the object.
Since we know that there is no net force acting on the body. Therefore, the force of friction is equal to 5 Newton.
a) Power is being used will be 12.5 Watts.
b) Force of friction is acting on the object will be 5 Newton.
What is the friction force?It is a type of opposition force acting on the surface of the body that tries to oppose the motion of the body. its unit is Newton (N).
Mathematically it is defined as the product of the coefficient of friction and normal reaction.
The given data in the problem is;
m is the mass of object =6.0 kg
u is the speed =2.5 m/s
a) Power is being used will be 12.5 Watts.
The distance traveled by the object is;
[tex]\rm d = v \times t \\\\ \rm d = 2.5 \times 25 \\\\ \rm d = 62.5 m[/tex]
The work done is the product of force and displacement;
[tex]\rm W = F \times d \\\\ \rm W = 5 \times 62.5 \\\\ \rm W = 312.5 \ J[/tex]
The power is the ratio of work done to the time;
[tex]\rm P= \frac{W}{t} \\\\ \rm P= \frac{312.5 }{25 } \\\\\ \rm P=12.5 \ Watt[/tex]
Hence Power is being used will be 12.5 Watts.
b) Force of friction is acting on the object will be 5 Newton.
If the all unbalanced force is zero the net force is equal to the force of friction;
The force of friction= Net force
Force of friction= 5 Newton.
Hence the force of friction is acting on the object will be 5 Newton.
To learn more about the friction force refer to the link;
https://brainly.com/question/1714663
