Answer:
to prevent the derailing of the train due to thermal expansion.
Answer:
Iron are good conductors of heat and electricity. Being a good conductor it expands as well as contracts with the change of temperature.When heat is applied,they expands because molecules inside the element gets excited and number of molecules inside it increases in tremendous amount,so it leads to expansion of iron. So when the temperature is lowered it comes in its normal state.
The term for this is called as thermal expansion or contraction.The gap in the joint between 2 rails is to prevent from the expansion of the iron. It is necessary ,if not there will be change in structure,it may buckle and chance of derailed is increased.
Explanation:
The gap in the joint between to rails is to compensate for the expansion of the material of rail during summer.
The metals expand or contract with the changes in temperature. The expansion or contraction depends on the coefficient of thermal expansion of the material. Based on this property of the metal, the gap in the joint of two rails is provided.
A lift that weighs 300 N moves a man with a weight of 950 N upwards by 12 m. How much work is done to move the lift this height?
The total work done to move the lift to this height if, A lift that weighs 300 N moves a man with a weight of 950 N upwards by 12 m, is 15000 Joules.
What is work done?When an object is moved over a distance by an external force, at least a portion of that force must be applied in the direction of the displacement. This is known as work in physics.
Given:
A lift that weighs 300 N moves a man with a weight of 950 N upwards by 12 m,
Calculate the total force as shown below,
Total force = Lift weight + man weight
Total force = 300 + 950
Total force = 1250 N
Calculate the work done as shown below,
The work done = Total force × displacement by total force
The work done = 1250 × 12
The work done = 15000 Joules
Thus, the total work done is 15000 joules.
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A 20 kg cart moving at 4 m/s has how much momentum?
40 kg*m/s
40 kg*m/s
5 kg*m/s
5 kg*m/s
80 kg*m/s
Answer:
We conclude that the required momentum is 80 kgm/s.
Explanation:
Given
Mass m = 20 kgVelocity v = 4 m/sTo determine
The momentum p = ?
Important Tip:
The momentum of an object is the product of mass and velocity.We can determine the momentum using the formula
[tex]p = mv[/tex]
where
p is the momentumm is the massv is the velocitynow substituting m = 20 and v = 4 using the equation
[tex]p = mv[/tex]
[tex]p = (20) (4)[/tex]
[tex]p = 80[/tex] kg m/s
Therefore, we conclude that the required momentum is 80 kgm/s.
The momentum of the moving cart is 80kgm/s.
HOW TO CALCULATE MOMENTUM:
The momentum of a body can be calculated by multiplying the mass of that body by its velocity. That is;Momentum (p) = mass (m) × velocity (v)
According to this question, a 20kg cart moving at 4 m/s will have a momentum as follows:Momentum (p) = 20kg × 4m/s
Momentum (p) = 80kg*m/s.
Therefore, the momentum of the moving cart is 80kgm/s.Learn more at: https://brainly.com/question/17173143?referrer=searchResults
Question 19 of 20
Planets A and B have the same size, mass, and direction of travel, but planet
A is traveling through space at half the speed of planet B. Which statement
correctly explains the weight you would experience on each planet?
A. You would weigh less on planet B because it is traveling twice as
fast as planet A.
B. You would weigh the same on both planets because your mass
would adjust depending on the planet's speed.
O C. You would weigh more on planet B because it is traveling twice as
fast as planet A.
D. You would weigh the same on both planets because their masses
and the distance to their centers of gravity are the same.
SUBMIT
Answer:
D. You would weigh the same on both planets because their masses
and the distance to their centers of gravity are the same.
Explanation:
The above statement is true due to the fact that, the weight and masses of the individual are same in direct comparison with the distance to their center of gravity. If the weight and masses are not same, then there would have been a significant difference between the two planet.
1. Why are the outer planets called “gas planets?”
Answer:
They are also called the gas planets because they consist mainly of hydrogen, or the giant planets because of their size. These planets usually have complicated system of many moons and often even rings of ice and/or dust. There are four Jovian planets in the Solar System: Jupiter, Saturn, Uranus and Neptune.
Answer:
They are also called the gas planets because they consist mainly of hydrogen, or the giant planets because of their size. These planets usually have complicated system of many moons and often even rings of ice and/or dust. There are four Jovian planets in the Solar System: Jupiter, Saturn, Uranus and Neptune.
Explanation:
i hope this helps :)
What do you understand if the frequency of a sound is 70 Hz?
Answer:
see below
Explanation:
frequency of a wave is the number of complete waves produced per second
so 70 Hz
means, that 70 complete waves are produced in one second,
hope this helps
14) What is the velocity of a wave 5.35 x 10 cm long with a frequency of 16kHz
Answer:
wavelength= 5.35×10cm=0.535m
f= 16000hz
v= wavelength × f= 0.535×16000=8560m/sec
On Earth, the gravitational field strength is 10 N/kg. Calculate E for a 4 kg bowling ball that is being
held 2 m above the ground
Answer:
People are exposed to sources of radiation in all aspects of everyday life. Radioactive sources can be very useful but need handling carefully to ensure safety.
Explanation:
need physics help
ASAP please!
Answer:
D
Explanation:
Fred is conducting a controlled experiment to test whether using a grow light at night will help a tomato plant grow faster. Below are the steps to Fred's experiment: Plant tomato plants in two separate, but identical, flowerpots. Place the flowerpots in the same area outside during the day. At night, bring both flower pots inside and place one in the dark and one under a grow light. Give the plants the same amount of food and water each week. Measure the growth of the plants. Draw conclusions based on the data collected. Which of the following variables must Fred hold constant in this experiment?
Answer:
the type of tomato plants used.
Explanation:
A pressure cooker has a mass of 1.5 kg and temperature of 30°C. The specific heat
capacity of the alloy from which the pressure cooker is made up of is 1000/kg
What will be its temperature when 7.5 *10') of heat is supplied to it?
Answer:
hjd
Explanation:
HELPPP PLEASE URGENT
A horizontal pipe of diameter 0.933 m has a smooth constriction to a section of diameter 0.5598 m. The density of oil flowing in the
pipe is 821 kg/m3. If the pressure in the pipe is 7220 N/m2 and in the constricted section is 5415 N/m2, what is the rate at which oil is flowing?
Answer in units of m3/s.
Answer:s
Explanation:
Write two characteristics of an educated society
Answer:
Different and better?
Explanation:
i dont think that helps lol
An educated person has the ability to think clearly and independently and has good judgement.
What is Education?Education is defined as purposeful activity directed towards achieving some objective, such as the dissemination of knowledge or the promotion of skills and character traits, whose aims include the development of understanding, rationality, kindness and honesty.
There are three main types of education which are as follows:
Formal, Informal and Non-formal.
The specialty of education is that it is pre-determined and pre-planned. It is regular and spatial i.e. time bound and regulated by the institutional. Proper education improves people's understanding of the world around them which make them less susceptible to the influence of others
Thus, an educated person has the ability to think clearly and independently and has good judgement.
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The body weighing 8kg moves in a straight line uniformly accelerated with an acceleration of 3m / s? on a horizontal surface, under the action of force 60N.Find a) What is the friction force acting on the body) The coefficient of friction between the body and the surface where it moves
Answer:
pls explain this to me
Explanation:
I will not answer it
both answers are here in the picture
The 25-mph zone is 150 yards long. How much time did the student save (in seconds) by speeding past the school
Answer:
Time = 12.27seconds
Explanation:
Given
Speed = 25miles/hour
Distance = 150 yards = 150(0.000568182)miles
Distance (in miles) = 0.0852273miles
Get the time
Speed = Distance/Time
Time = Distance/Speed
Time = 0.0852273/25
Time = 0.0034hours
Time = 0.0034 * 3600secs
Time = 12.27seconds
Being overweight or obese increases the risk of:
A. Diabetes
B. Heart disease
C. Stroke
D. All of the above.
theanswer is b.heart disease
An ambulance siren has a frequency of 650 Hz and is moving away from you at 35 m/s. What frequency will you perceive? Use 346 for the speed of sound.
590 Hz is the answer to the question
An ambulance siren has a frequency of 650 Hz and is moving away from you at 35 m/s. What frequency will you perceive? Use 346 for the speed of sound.
Answer:
59.71 Hz
Explanation:
Frequency: 650 Hz
Velocity: 35 m/s
Speed of sound: 346
f = f(v / v + speed of sound)
f = 650(35 / 35 + 346)
Evaluate and you would perceive a frequency of 59.71 Hz
6. Compare Which of the
following can carry the
most current?
a. 9-V battery
b. 220-V electrical outlet
c. 12-V battery
d. 110-V electrical outlet
What is the kinetic energy of a 2.1kg baseball and is traveling at 10 m/s?
Answer:
Explanation:
KE = 1/2mv^2
KE = 1/2(2.1)(10)^2
KE=105N
Anyone knows this? Please answer... Spam will be reported.
Answer:
The correct option is;
The assertion is correct, but reason wrong
Explanation:
The question is with regards to the relationship between work, energy, power, and velocity
The mass of each of the persons running up the staircase = Different
The time it takes each person to run up the stairs = Equal time
Let, 'm₁' and 'm₂' represent the mass of each of the persons that ran up the stairs and m₁ > m₂
Let 't' represent the equal time it takes then to run up the stairs
Let 'h' represent the height of the stairs
The energy, 'E', it takes to run up the stairs is equal to the potential energy, P.E., obtained at the top of the stairs
P.E. = m·g·h
Where;
m = The mass of the person at an elevated height
g = The acceleration due to gravity = Constant
h = The height reached above ground level
Given that the height reached is the same for both of the persons, we have
For m₁, P.E.₁ = m₁·g·h and for m₂, P.E.₂ = m₂·g·h
Therefore, where, m₁ > m₂, we have;
P.E.₁ > P.E.₂
∴ E₁ > E₂
Power, 'P', is the rate at which energy is expended
∴ Power, P = E/t
∴ P₁ = E₁/t > P₂ = E₂/t
Therefore, the person with the greater mass, 'm₁', uses more power than the person of mass 'm₂', in running up the stairs
Therefore, the assertion is correct
The average velocity, vₐ = (Total distance traveled, d)/(Total time taken, t)
Given that the distance, 'd', covered in running up the stairs by both persons is the same, and the time it takes them to complete the distance, 't', is also the same, we have;
The average velocity of the person with the greater mass m₁ is the same as the average velocity of the person with mass, m₂
Therefore, the reason is wrong
The answer is that the assertion is correct, but reason wrong
What is the kinetic energy of a 0.500 kg toy car moving at a state of 1.50 m/s
Answer:0.563
Explanation:
The kinetic energy produced in a toy car is equal to 0.563 J.
What is the kinetic energy and potential energy?The energy exhibited by a moving body because of its motion is said to be its kinetic energy. Work should be done which can change the kinetic energy of a moving object.
The kinetic energy of a moving object can be determined from the formula mentioned below:
K.E. = ½mv² where ‘m’ and ‘v’ is the mass, velocity of the object.
Potential Energy (P.E.)is energy that is stored in an object due to its position and can be expressed as P.E = mgh where h, m, and g are the height, mass, and gravitational acceleration respectively.
Given, the mass of the toy car =, m = 0.500 Kg
The velocity of the toy car, v = 80 m/s
The kinetic energy = (1/2)× 0.500 ×(1.50)²
K.E. = 0.563 J
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Explain the difference between mass and weight. Also, what happens to your mass and your weight if you were to travel to the moon? Why?
PLEASE HURRY!!
The brakes of a lorry are in a poor condition
What effect will the condition of the brakes have on thinking distance and the braking
distance of the lorry?
Answer:
friction
Explanation:
Her brakes will squeak and possibly slide or skid on concrete due to her brakes.
BUT it really depends on the condition of the wheels. Now it matters on the surface as well. Has the road been eroded? what has happened with her brakes? and what texture are the wheels? can seismic waves travel through them?
Answer:
thinking distance stays the same and the braking distance increases
AQA Approved.✅
Explanation:
yo pls help me I'm desperate lowkey
Why is it safer to collide with a soft cushion than a hard surface?
Answer:
Impulse is force multiplied by time; and together, the product must be 1 unit. A collision with soft ground will result in the 1 unit of impulse by a larger time and a smaller force (compared to the small time and a large force for the hard floor).
24 How long does it take for the Earth to orbit the Sun?
A one day
B one week
C one month
D one year
Answer:
365 days
So The Final Answer is a Year
D is the answer
Explanation:
Answer:
C one month
Explanation:
pls help me i will name brainliest
Answer:
a for the first one b for the second
What is the Kinetic Energy of a 120 kg object that is moving with a velocity of 15 m/s
Answer:
Kinetic Energy:120 x 15=1800
Explanation:
Answer:
13500J
Explanation:
Kinetic energy = (1/2×120)kg × (15m/s)^2
KE = 60kg × 225 (m/s)^2 = 13500J
why sounds hear clearly at night than day?
No one give proper answer.
when you carry the 2 and add the 3 its Z
PLEASE HELP!!! GIVING BRAINLIEST!! ill also answer questions that you have posted if you answer this correctly!!!! (40pts)
Answer:
Explanation:
According to this site, "The purpose of these curved wingtips is to prevent high air pressure above the airplane from flowing over and under the wings."
Hope this helps!