Answer:
v = 27 m/s
Explanation:
To find the speed of cars after the collision you take into account the momentum conservation law. Total momentum of both cars before the collision must be equal to the total momentum of both cars after the collision.
After the collision both cars traveled together, then you have:
[tex]m_1v_1+m_2v_2=(m_1+m_2)v[/tex] (1)
m1: mass of the Toyota = 3-ton = 3000 kg
m2: mass of the taxi = 2-ton = 2000kg
v1: speed of the Toyota before the collision = 45m/s
v2: speed of the car before the collision = 0 m/s (it is at rest)
v: speed of both cars after the collision = ?
You solve the equation (1) for v:
[tex]v=\frac{m_1v_1+m_2v_2}{m_1+m_2}[/tex]
Next, you replace the values of the rest of the variables:
[tex]v=\frac{(3000kg)(45m/s)+0kgm/s}{3000kg+2000kg}=27\frac{m}{s}[/tex]
hence, just after the collision both cars have a speed of 27m/s
A home uses about 4*10^11 power joules of energy each year. In many parts of the United States there are about 3000 h of sunlight each year. How much energy from the sun falls on one square meter each year? If the solar energy can be converted to useful energy with an efficiency of 20%, how large an area of converters would produce the energy needed by the home?
Answer:
The Sun transfers in each second and amount of 1367J per square meter, so in hour it can transfer:
E = 60*60*1367 J/h*m2 = 4,921,200 J/h*m^2.
in one year, we have 3000h*4,921,200 J/h*m^2. = 14,763,600,000 Joules per square meter.
Now, only 20% of this can be used as energy, so the amount that can be used is:
E = 0.2* 14,763,600,000 J/m^2 = 2,952,720,000 J/m^2
Now, we want to find the number X of square meters such:
X*2,952,720,000 J/m^2 = 4x10^11 J
X = ( 4x10^11 J)/(2,952,720,000 J/m^2) = 135.5 m^2
So you only need around 135.5 square metters per house.
is the thermal energy transferred in a refrigerator primarily by conduction,convection or radiation? explain your answer
Answer: Convection
Explanation: convection is the most present process in the refrigeration equipment you may deal with. It occurs mainly in the fluids
Did Lydia make an all-or-nothing or a marginal decision while spending her money? Justify your response.
Answer:
Lydia made a marginal decision because she is trying to save for her collage by spending less, she will have some money left over after paying for her necessary to go to her college tuition.
Explanation:
She saved part of it for her college tuition and spent the remainder for the prom dress, car insurance, and birthday gift.
Did Lydia make an all-or-nothing or a marginal decision while spending her money so that she can save some money for her college, that was why she was spending less.
What is marginal decision?
Marginal decision can be regarded as the decision that can be made by regarding one additional unit of a good.
Therefore , that was what Lydia was trying to do by by comparing the marginal cost and marginal benefit associated with her college and what she was buying.
Read more on the marginal decision here:
https://brainly.com/question/17230008
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3 differences between heat and temperature
Answer:
Difference Between Heat and Temperature
heat vs temperature The concept of heat and temperature are studied together in science, which is somewhat related but not alike. The terms are very common, due to their wide usage in our day to day life. There exist a fine line which demarcates heat from temperature, in the sense that heat is thought of, as a form of energy, but the temperature is a measure of energy.
The differences between heat and temperature can be summarised in points as follows:
Heat1.Heat is the form of energy that flows from the system to its surrounding.
2. Mass of the body affects the total heat.
3. Heat is measured in joules or calories.
4.2Joules =1 calorie
4. Heat is measured by using a calorimeter.
TemperatureTemperature is the result of heat.Mass of the body does not effect on temperature but depends on the molecular vibration of the body.Temperature is measured in degree, Celsius or degree Fahrenheit or Kelvin scale.Temperature is measured by using thermometer.Hope it helps...
Good luck on your assignment...
8. An object starts from rest and accelerates at
1.30 m/s2 [N] for 6.00 s. What is the final
velocity of the object?
need help
Answer:
here is the answer
Explanation:
initial velocity= u= 0
final velocity = v
acceleration= 1.30m/s²
time= 6 seconds
using formula
a = v-u/t
1.30 = v - 0/6
1.30*6 = v - 0
7.8= v - 0
7.8 = v
therefore, final velocity is 7.8 m/s
A positive charge of 1 µC is taken from points A & B such that VA-VB = 100 V. Then the
energy of charge increases by 10-3 J
energy of charge decreases by 10-3 J
energy of charge remains unchanged
energy of charge decreases by 103
Explanation:
It is given that,
Let Charge of [tex]1\ \mu C[/tex] is taken from points A & B such that [tex]V_A-V_B=1000\ V[/tex].
We need to find the energy of charge. Electric potential is defined as the work done per unit of electric charge. So,
[tex]W=(V_B-V_A)q\\\\W=-1000\times 10^{-6}\\\\W=E=-10^{-3}\ J[/tex]
So, the energy of charge decreases by [tex]10^{-3}\ J[/tex]. Hence, the correct option is (a).
If an atom loses two electrons what charge will it have?
+1
-1
+2
-2
Answer:
+2
Explanation:
Because electrons are negative so if electrons are lost then it will automatically become positive in this case +2. This will be right if there are then more electrons than protons in total. I pretty sure it's correct.
what is the charge of a newly formed oxygen ion
The charge of a newly formed oxygen ion would be -2
Hope this helps :)
What is the potential energy of a 3 kg rock sitting at the top of a 21 meter high cliff?
Answer:
618.03 J
Explanation:
Potential energy can be calculate using the following formula.
PE=m*g*h
where m is the mass, g is the acceleration due to gravity and h is the height.
In this situation, we have a 3 kilogram rock on a 21 meter high cliff. Therefore, the mass is 3 kg and the height is 21 m.
On Earth, the acceleration due to gravity is 9.81 m/s^2.
m=3 kg
h=21 m
g=9.81 m/s^2
Substitute these values into the formula.
PE=3*9.81*21
Multiply all the numbers together
PE=63*9.81
PE=618.03
The potential energy is 618.03 kg m^2/s^2, or 618.03 Joules
If you apply a force of 75N to an object and you generate an acceleration of 25 m/s^2. What is the mass of the object? (Use Second Law of Newton)
Answer:
m = 3 kg
Explanation:
It is given that,
Force applied to the object is 75 N
Acceleration generated in the object is, [tex]a=25\ m/s^2[/tex]
We need to find the mass of the object. The force acting on an object is given by the Newton's second law of motion.
Force F=ma
[tex]m=\dfrac{F}{a}\\\\m=\dfrac{75}{25}\\\\m=3\ kg[/tex]
So, the mass of the object is 3 kg.
a footballer took a penalty kick and ball moved with a velocity of 4mls, calculate the work done by the footballer if the mass of the ball was 40g
Answer:
Work done = 80 gm/s
Explanation:
Given:
Final velocity (v) = 4 m/s
Initial velocity (u) = 0 m/s
Mass of ball (m) = 40 g
Find:
Work done.
Computation:
Using work energy rule
Work done = Change in kinetic energy
Work done = 1/2[mv-mu]
Work done = 1/2[(40)(4) - (40)(0)]
Work done = 1/2[(40)(4)]
Work done = 80 gm/s
Can someone please help meee!!
A mass of 2000 kg is raised 5.0 min 10 seconds. What is the power output to raise the object?
9,800,000 J/s
49,000 J/s
1000 J/s
9800 J/S
The answer is 9800 J/S
Answer:
9800 J/s
Explanation:
Match the labels: 1. forces 2.magnetic fields 3.electric fields 4.gravitational fields
a ladybug falls into small hole. it takes 8.6s for the ladybug to hit the bottom. how deep is the hole? (take g=9.81 m/s²)
A small object is placed on the principal axis of a convex mirror of focal length 10cm . Determine the position of the image when the object is 15cm from the mirror.
Answer:
v = 6 cm
Explanation:
We have,
A small object is placed on the principal axis of a convex mirror of focal length 10 cm. The focal length of a convex mirror is positive. So, f = +10 cm
It is required to find the position of the image when the object is 15 cm from the mirror. Using mirror's formula :
[tex]\dfrac{1}{v}+\dfrac{1}{u}=\dfrac{1}{f}[/tex]
v is image distance
[tex]\dfrac{1}{v}=\dfrac{1}{f}-\dfrac{1}{u}\\\\\dfrac{1}{v}=\dfrac{1}{+10}-\dfrac{1}{(-15)}\\\\v=6\ cm[/tex]
Hence, the image will formed at a distance of 6 cm form the mirror.
what is the method of charging used when you run a straw with fur
Answer:
charging by friction
Explanation:
Friction is another method of making a charge become higher than the other.
With either straw or a fur,charging by friction is used.
Which food provides the body with energy in the form of carbohydrates
Grains, pasta, etc provides the body with energy in the form of carbohydrates because they're absorbed quickly by the body and used for energy.
why might the study of matter and energy be important
Answer:
The flow of matter and energy in the ecosystems is important so that the exchange necessary for them to work. In order for ecosystems to exist, there must be energy flowing and making possible the transformation of matter. Ecosystems are complex systems that exchange matter and energy with the environment and, as a result, modify it.
Explanation:
According to the law of reflection, the angle at which light strikes a surface is
the angle at which light is reflected.
a. the same as
c. less than
b. slightly larger than
d. much larger than
Answer:
Option a
Explanation:
The light that strikes this surface is referred to as the incident ray, and the light reflected is referred to as the reflected ray - as one might have guessed. Respectively, the angle with which the incident ray struck the surface is known as the " incident angle, " while the angle with which the reflected ray reflects off this surface is known as the " angle of reflection. "
_______________________________________________________
By the law of reflection, you would say that the incident angle is equal to the angle of reflection. Thus, the answer is option a.
Hope that helps!
Marie lifts a 5 kg mass from the floor and puts in on a table one metre high. What is the work done?
Answer:
The work done was 49.05 N*m.
Explanation:
The work done by a a force is given by:
[tex]W = F*d[/tex]
We first need to calculate the force necessary to lift the box from the ground, the force needed for is the weigh of the box, which is shown below:
[tex]F = m*g\\F = 5*9.81\\F = 49.05 \text{ N}[/tex]
Therefore the work done by lifting the box and placing it on the table is:
[tex]W = 49.05*1 \\W = 49.05 \text{ N*m}[/tex]
The work done was 49.05 N*m.
What is Elasticity? (best answer will get marked brainliest)
Answer:
In economics, elasticity is the measurement of the percentage change of one economic variable in response to a change in another.
An elastic variable (with an absolute elasticity value greater than 1) is one which responds more than proportionally to changes in other variables. In contrast, an inelastic variable (with an absolute elasticity value less than 1) is one which changes less than proportionally in response to changes in other variables. A variable can have different values of its elasticity at different starting points: for example, the quantity of a good supplied by producers might be elastic at low prices but inelastic at higher prices, so that a rise from an initially low price might bring on a more-than-proportionate increase in quantity supplied while a rise from an initially high price might bring on a less-than-proportionate rise in quantity supplied.
Elasticity can be quantified as the ratio of the percentage change in one variable to the percentage change in another variable, when the latter variable has a causal influence on the former. A more precise definition is given in terms of differential calculus. It is a tool for measuring the responsiveness of one variable to changes in another, causative variable. Elasticity has the advantage of being a unitless ratio, independent of the type of quantities being varied. Frequently used elasticities include price elasticity of demand, price elasticity of supply, income elasticity of demand, elasticity of substitution between factors of production and elasticity of intertemporal substitution.
Elasticity is one of the most important concepts in neoclassical economic theory. It is useful in understanding the incidence of indirect taxation, marginal concepts as they relate to the theory of the firm, and distribution of wealth and different types of goods as they relate to the theory of consumer choice. Elasticity is also crucially important in any discussion of welfare distribution, in particular consumer surplus, producer surplus, or government surplus.
In empirical work an elasticity is the estimated coefficient in a linear regression equation where both the dependent variable and the independent variable are in natural logs. Elasticity is a popular tool among empiricists because it is independent of units and thus simplifies data analysis.
A major study of the price elasticity of supply and the price elasticity of demand for US products was undertaken by Joshua Levy and Trevor Pollock in the late 1960s..
Answer:
the quality of that something have been able to stretch to its original shape
A 2.50 kg object is held 2.10 m above the ground. What is the gravitational potential energy of the object with respect to the ground?
Answer:
USAS LA FÓRMULA DE ENERGÍA POTENCIAL
Explanation:
U = 2.50 kg([tex]9.80 m/s^{2}[/tex])(2.10 m) = 51.45 J
What is work done in physics?
Answer:
work done is the product of force and distance moved in the direction of a force
Answer:
work is said to be done when an energy or force is used.
Explanation:
when you carry a cement and you take a step, work is done.
the figure shows an initially stationary block of mass m on a floor. A force of magnitude 0.500mg is then applied at upward angle θ= 20∘. What is the magnitude of the acceleration of the block across the floor if the friction coefficients are (a) μs=0.610 and μk=0.500 and (b)μs=0.400 and μk=0.300
Answer:
(a) 1.054 m/s²
(b) 1.404 m/s²
Explanation:
0.5·m·g·cos(θ) - μs·m·g·(1 - sin(θ)) - μk·m·g·(1 - sin(θ)) = m·a
Which gives;
0.5·g·cos(θ) - μ·g·(1 - sin(θ) = a
Where:
m = Mass of the of the block
μ = Coefficient of friction
g = Acceleration due to gravity = 9.81 m/s²
a = Acceleration of the block
θ = Angle of elevation of the block = 20°
Therefore;
0.5×9.81·cos(20°) - μs×9.81×(1 - sin(20°) - μk×9.81×(1 - sin(20°) = a
(a) When the static friction μs = 0.610 and the dynamic friction μk = 0.500, we have;
0.5×9.81·cos(20°) - 0.610×9.81×(1 - sin(20°) - 0.500×9.81×(1 - sin(20°) = 1.054 m/s²
(b) When the static friction μs = 0.400 and the dynamic friction μk = 0.300, we have;
0.5×9.81·cos(20°) - 0.400×9.81×(1 - sin(20°) - 0.300×9.81×(1 - sin(20°) = 1.404 m/s².
Spaceship 1 and spaceship 2 have equal masses of 150kg. Spaceship 1 has the speed of 0 m/s and spaceship 2 has a speed of 6 m/s. They collide and stick together and what is their speed ?
Answer:
3 m/s
Explanation:
The computation of speed is shown below:-
We will compute the equation by using the law of conservation of momentum; also, the total momentum prior and following the collision must be conserved. Therefore we can write the equation is the following manner:-
[tex]m_1 u_1 + m_2 u_2 = (m_1 +m_2)v[/tex]
where the symbols represent
150 kg is the mass of spaceship 1 = m1
150 kg is the mass of spaceship 2 = m2
0 m/s is the initial velocity of spaceship 1 = u1
6 m/s is the initial velocity of spaceship 2 = u2
and v is the velocity of the 2 ships so that they can collide and combined together
For v we will get the following equation to reach the speed
[tex]v=\frac{m_1 u_1 + m_2 u_2}{m_1+m_2}[/tex]
[tex]=\frac{0+(150)(6)}{150+150}[/tex]
[tex]=3 m/s[/tex]
The kinetic theory is useful for a explaining how matter and energy are not always related. b testing the temperature of a gas. c determining how much heat is necessary to melt a solid. d showing the differences between states of matter.
Answer:
showing the differences between states of matter.
Answer:
D
Explanation:
the kinetic theory of matter states that matter is made up of molecules that are in continuous motion.this in turn talks about the different states of matter
An electric pole casts a shadow of 24 m long . If the tip of the shadow is 25m far from the top of the pole , how high is the pole?????
Answer:
7 m
Explanation:
a^ + b^=c^
a^ + 24^=25^
a^+576=625
a^=625-576
a^=49
a=7
The de Broglie relation λ=h/p can be rewritten in terms of the wave number k as p=kℏ. Recall that wave number is defined by k=2π/λ. Using the fact that λ=v/f, find the wave numbers k1 and k2 corresponding to frequencies f1 and f2. Express your answer as two expressions
Answer:
k₁ = 2πf₁/v
k₂ = 2πf₂/v
Explanation:
Since the de Broglie relation λ=h/p (1 ) and momentum, p =kℏ (2)
From (1) p = h/λ = kℏ
So, h/λ = kℏ
Hence, k = h/ℏλ since ℏ = h/2π and wavelength, λ = v/f, substituting these two into k, we have
k = h/[(h/2π)(v/f)]
k = 2πf/v where k = wave number, f = frequency of wave and v = velocity of wave.
Now, for the first wave number k₁, k₁ = 2πf₁/v
for the second wave number k₂, k₂ = 2πf₂/v
If you push on a wall of a building what will happen
Answer: It will push back with an equal amount of force.
A ramp with a mechanical advantage of 4 is used to move a 38-newton load. What
effort force is needed to push the load up the ramp?
A.9.5 N
B.15.2N
C.3.9 N
D.0.11 N
Explanation:
It is given that,
Mechanical advantage of a ramp is 4
It is used to move a 38 N load
We need to find the force needed to push the load up the ramp. The mechanical advantage is equal to the ratio of output force to the input force. We have output force as 38 N
So,
[tex]4=\dfrac{38}{F_i}\\\\F_i=\frac{38}{4}\\\\F_i=9.5\ N[/tex]
So, the force of 9.5 N is needed to push the load up the ramp.