Answer:
a) v₀ = 2.5 m / s, heading south.
b) W = 1,219 10⁵ J
Explanation:
a) For this exercise we can use the conservation of the moment, we create a system formed by all the 4 cars, in this case when the last one separates the forces are intense and the moment is conserved
initial instant. Before separation
p₀ = M v₀
final instant. When uncoupling the last car
p_f = 3m v₁ + m v₂
where they indicate that the speed of the wagons is v₁ = 2.00 m / s and the speed of the last wagon is v₂ = 4.00 m / s
the total mass is M = 4m
how the moment is preserved
p₀ = p_f
4m v₀ = 3m v₁ + mv₂
v₀ = ¾ v₁ + v₂ / 4
let's calculate
v₀ = ¾ 2 + ¼ 4
v₀ = 2.5 m / s
heading south.
b) work is equal to the change in kinetic energy
W = ΔK = K_f -K_o
W = ½ m v_f² - ½ m v₀²
W = ½ m (v_f² -v₀²)
W = ½ 2.50 10⁴ (4² - 2.5²2)
W = 1,219 10⁵ J
Outline 3 disadvantages and advantage of water and alcohol as a template liquid
Answer:
Advantages of mercury as a thermometric liquid.
-It is a good conductor of heat and therefore the whole liquid reaches the temperature of the surroundings quickly.
-It does not wet (cling to the sides of) the tube.
-It has a high boiling point
-It expands uniformly (linear expansion) and responds quickly to temperature changes, hence is sensitive.
-It has a visible meniscus.
Disadvantages
-Mercury is very poisonous.
-its expansively is fairly low
-it is expensive
-It has a high freezing point therefore it cannot be used in places where the temperature gets very low.
Alcohol has a thermometric fluid
-Alcohol expands uniformly.
-It has a low freezing point (-115 degreecentigrade) therefore it is very suitable for place where the temperature gets very low.
-It has a large expansively
-It is an easily available cheap liquid, which is safe to use
Disadvantages of alcohol
-it wets the tube
-it has a low boiling point (cannot be used in places with high temperatures)
-it does not react quickly to changes in temperature
-It needs to be dyed, since it's colourless.
Disadvantages of water
-Water has high specific heat capacity. So it cannot be used for measuring small temperature differences.
- Water will wet the surface of the glass tube. It is a sticky substance.
- Water is transparent
Explanation:
A baseball is traveling (+30m/s) and is hit by a bat. It leaves the bat traveling (−40m/s). What is the change in its velocity?
Unlike some others, this is any choice, so not just 4 choices!
Answer:
Explanation:
The change must be 30 - - 40 which means it came in a 30 meters / second and went out in the opposite direction at 40 meters / second
The change is 70 m/sec.
You could show it to be - 70 meters per second as well. That's done by making the outgoing direction minus.
Delta v = vf - vi.
Now it depends on which way you define vf and vi.
PLEASE HELP ME WITH THIS ONE QUESTION
1000 J of energy is given to a balloon via a heating device. Assuming the pressure is a constant 101,325 Pa, what is the final volume of the balloon, assuming it started at 0.001 m3?
Answer:
Vf = 0.0108 m³
Explanation:
Assuming there is no change in internal energy, we can calculate the changed volume by the following formula:
[tex]Energy\ Supplied = Work = W = P \Delta V \\W = P(V_{f}-V_{i})\\[/tex]
where,
W = Work = Energy Supplied = 1000 J
P = Pressure = 101325 Pa
Vf = Final Volume = ?
Vi = Initial Volume = 0.001 m³
Therefore,
[tex]1000\ J = (101325\ Pa)(V_{f}-0.001\ m^3)\\\\V_{f}-0.001\ m^3 = \frac{1000\ J}{101325\ Pa}\\\\V_{f} = 0.001\ m^3 + 0.0099\ m^3[/tex]
Vf = 0.0108 m³
A 1.6 kg ball is attached to the end of a 0.40 m string to form a pendulum. This pendulum is released from rest with the string horizontal. At the lowest point of its swing, when it is moving horizontally, the ball collides with a 0.80 kg block that is at rest on a horizontal frictionless surface. The speed of the block just after the collision is 3 m/s. What is the speed of the ball just after the collision
Answer:
the speed of the ball just after the collision is 1.5 m/s.
Explanation:
Given;
mass of the ball, m₁ = 1.6 kg
initial velocity of the ball, u₁ = 0
mass of the block, m₂ = 0.8 kg
initial velocity of the block, u₂ = 0
final velocity of the block, v₂ = 3 m/s
let the final velocity of the ball after collision = v₁
Apply the principle of conservation of linear momentum for elastic collision;
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂
1.6 x 0 + 0.8 x 0 = 1.6 x v₁ + 0.8 x 3
0 = 1.6v₁ + 2.4
-1.6v₁ = 2.4
v₁ = -2.4 / 1.6
v₁ = - 1.5 m/s
v₁ = 1.5 m/s (in opposite direction of the block)
Therefore, the speed of the ball just after the collision is 1.5 m/s.
4. If the cooling of magma takes place slowly beneath Earth's surface, the rock is that is formed
is called
a. extrusive igneous rock
b. intrusive igneous rock
c. sedimentary rock
d. metamorphic rock
Which of the following is an example of the transformation of gravitational potential energy into motion energy (kinetic energy)?
Answer:
c
Explanation:
because a drop of water is falling and that is gravitational potential energy into motion energy
what is the reason for timing more than one oscillation in a simple pendulum
Answer:
Time period is the time taken by the body to complete one oscillation and it is noted more than once to get accurate reading from averaging of all the observed values.
how much force is needed to accelerate a 2500kg car at a rate of 4m/s2
Answer:
10,000 N
Explanation:
Using Newton's Second Law of Motion, Force = Mass*Acceleration.
Plugin 2500 kg for the mass and 4 m/s^2 for the acceleration.
Force = 2500 kg*4 m/s^2 = 10000 Newtons
(SI unit of force is Newtons)
A young parent is dragging a 65 kg (640 N) sled (this includes the mass of two kids) across some snow on flat ground, by means of a rope attached to the sled. The rope is at an angle of 30 degrees with respect to the ground and the tension in the rope is 160 N. The sled is moving at a constant velocity of 1.5 m/s.
(a) Draw and label all forces acting on the kids + sled system. Indicate the relative size of each force by scaling the length of each force arrow appropriately
(b) Calculate the normal force acting on the system
(c) Calculate the force of friction acting on the system.
(d) Calculate the coefficient of friction between the sled and the snow.
Answer:
b) N = 560 N, c) fr = 138.56 N, d) μ = 0.247
Explanation:
a) In the attachment we can see the free body diagram of the system
b) Let's write Newton's second law on the y-axis
N + T_y -W = 0
N = W -T_y
let's use trigonometry for tension
sin θ = T_y / T
cos θ = Tₓ / T
T_y = T sin θ
Tₓ = T cos θ
we substitute
N = W - T sin 30
we calculate
N = 640 - 160 sin 30
N = 560 N
c) as the system goes at constant speed the acceleration is zero
X axis
Tₓ - fr = 0
Tₓ = fr
we substitute and calculate
fr = 160 cos 30
fr = 138.56 N
d) the friction force has the formula
fr = μ N
μ = fr / N
we calculate
μ = 138.56 / 560
μ = 0.247
In fatal crashes, more than __________% of passenger car occupants who were totally ejected from the vehicle were killed.
Answer:
it would be 83% in a fatal crash.
The force of friction depends upon
Answer:
ask internet?
Explanation:
easy .....
..
A capacitor is made from two hollow, coaxial, iron cylinders, one inside the other. The inner cylinder is negatively charged and the outer is positively charged; the magnitude of the charge on each is 11.5 pC. The inner cylinder has a radius of 0.550 mm, the outer one has a radius of 7.20 mm, and the length of each cylinder is 13.0 cm.
(a) What is the capacitance?
(b) What applied potential difference is necessary to produce these charges on the cylinders?
Answer:
A)2.811 × 10^-12 F
B)4.09V
Explanation:
(a) What is the capacitance?
Capacitance of coaxial cylinder can be determined using below expresion
C= (2π ε0 L)/ Ln[ rb/ra]
Where
ε0= permittivity of free space= 8.85×10^−12 Fm^-1
L= length of each cylinder =13.0 cm= 13×10^-2m
rb= radius of outer cylinder= 7.20 mm= 7.20×10^-3m
ra=radius of inner cylinder=0.550 mm= 0.550×10^-3 m
If we substitute the values we have,
C= (2π ε0 L)/ Ln[ rb/ra]
C= ( 2 × π × 8.85×10^−12 ×13×10^-2) / Ln[
7.20×10^-3/0.550×10^-3]
C=( 7.2288×10^-12 )/2.5729
C=2.811 × 10^-12 F
B) (b) What applied potential difference is necessary to produce these charges on the cylinders?
Vba= Q/C
Where Vba=potential difference
Q= charge on each = 11.5 pC. = 11.5×10^-12
C= capacitance= 2.811 × 10^-12 F
If we substitute the values we have
Vba=(11.5×10^-12)/2.811 × 10^-12
= 4.09V
C
D
7
The sun is the original source of
energy for many of our energy
resources
Which energy resource does not
originate from the sun? *
(1 Point)
.
A. Geothermal
B. Hydroelectric
C. Waves
D. Win
Answer:
geothermal
Explanation:
geothermal energy is the heat energy obtained from within the Earth. Hence not derived from Sun's energy.
faraday's law states that the potential difference can be increased by... (choose all that apply)
1. using static electricity instead of current electricity
2. increase the number of coils, increase the strength of the magnet
3. using a bunch of small magnets
4. increasing the time used to power up an electromagnet
5. increase the speed of the magnet
Id say its the last option of the fourth option
Explanation:
Answer:
1:increase the number of coils, increase the strength of the magnet
2:increase the speed of the magnet
3: increasing the time used to power up an electromagnet
Explanation:
1). Increasing the number of turns of wire in the coil – By increasing the amount of individual conductors cutting through the magnetic field, the amount of induced emf produced will be the sum of all the individual loops of the coil, so if there are 20 turns in the coil there will be 20 times more induced emf than in one piece of wire.
2). Increasing the speed of the relative motion between the coil and the magnet – If the same coil of wire passed through the same magnetic field but its speed or velocity is increased, the wire will cut the lines of flux at a faster rate so more induced emf would be produced.
3). Increasing the strength of the magnetic field – If the same coil of wire is moved at the same speed through a stronger magnetic field, there will be more emf produced because there are more lines of force to cut.
What is Gravity?
PLEASE ANSWER
Answer:
Gravity is the force by which a planet or other body draws objects toward its center. The force of gravity keeps all of the planets in orbit around the sun.
Please mark as brainliest
Have a great day, be safe and healthy
Thank u
XD
Answer:
GRAVITY:
In physics, gravity is the force that attracts a body towards the centre of the earth, or towards any other physical body having mass.
You hold your physics textbook in your hand. (Assume that no other objects are in contact with the book.)
a. Identify the forces acting on the book.
1. book on hand
2. hand on book
3. floor on book
4. earth on book
b. For each force you identified in part (a), indicate the direction. (If a force is not applicable, choose NA.)
1, book on hand __________
2. hand on book __________
3. floor on book __________
4. earth on book _________
Answer:
a) Please see below as the answer is self-explanatory.
b) 1. vertically downward
2. vertically upward
3 N/A
4 vertically downward.
Explanation:
a)
If the book is hold by the hand, this means (according to Newton's third law) that both exert a force on each other, equal and opposite.In this case this pair is formed by normal forces, the normal force (upward) that the hand does on the book (avoiding it to be accelerated downward) and the normal force that the book does on the hand (downward) avoiding it to be accelerated in the upward direction.The other force that acts on the book is the one due to gravity, and is always downward, which is numerically equal to the normal force that the hand does on the book, due to the book is at rest. There is no interaction between the book and the floor, so there is no force between them, neglecting the gravitational attraction between their masses.What is the magnitude of the resultant vector? Round
your answer to the nearest tenth.
m
R
5 m
13 m
Intro
Done
Answer: 13.9 m
Explanation:
Answer:
13.9m
Explanation:
Answer on Edge
ball A is dropped from a hot air balloon rising at a costant velocity of 14,7 m.s'1 at a height of 19,7 m above the ground.the ball took 1.5s to reach its maximum height and hits the ground after some time in air.ignore the effects of air resistanceUse the ground as zero reference.3.1.1calculate the maximum height reached by the ball above the ground
Answer:
this slow site thinks the answer is a link
Explanation:
this was a week ago so i dont know if u still need help
3. A backpack weighs 8.2 N and has a mass of 5 kg on the moon. What is t
strength of gravity on the moon?
8.2 N
A student sets up a standing wave of wavelength 6 meters in a coiled spring by moving his hand up and down twice each second. What is the velocity of the wave?
Answer:
Velocity = 12 m/s
Explanation:
Given the following data;
Wavelength = 6 meters
Period = 0.5 seconds. This is due to the fact that the student is moving his hand up and down twice each second.
To find the velocity;
Velocity = wavelength * frequency
But, frequency = 1/period
Frequency = 1/0.5
Frequency = 2
Substituting the values into the velocity formula, we have;
Velocity = 6 * 2
Velocity = 12 m/s
Therefore, the velocity of the wave is 12 meters per seconds.
An elevator motor in a high-rise building can do 3500 kJ of work in 5 min. Find the power developed by the motor. Explain if you can plz
Answer:
P = 11666.6 W
Explanation:
Given that,
Work done by the motor, W = 3500 kJ
Time, t = 5 min = 300 s
We need to find the power developed by the motor. Power developed is given by :
[tex]P=\dfrac{E}{t}\\\\P=\dfrac{3500\times 10^3}{300}\\\\P=11666.7\ W[/tex]
So, the required power is 11666.6 W.
What color is a carrot?
Answer:
reddish-orrange
Explanation:
please mark me as brainliest
Identify equivalent terms for stored energy and energy of motion.
a. Stored energy is potential energy, and energy of motion is kinetic energy.
b. Energy of motion is potential energy, and stored energy is kinetic energy.
c. Stored energy is the potential as well as the kinetic energy of the system.
d. Energy of motion is the potential as well as the kinetic energy of the system.
Answer:
a. Stored energy is potential energy, and energy of motion is kinetic energy
Explanation:
The correct option is - a. Stored energy is potential energy, and energy of motion is kinetic energy.
Reason -
Potential energy is stored energy, whereas kinetic energy is the energy of moving things.
Kinetic energy is energy possessed by an object in motion.The energy associated with position is called potential energy .A baseball is thrown a distance of 20 m what is its speed if it takes 0.5 seconds to cover the distance
Answer:
40m/s
Explanation:
Young's double slit experiment is one of the quintessential experiments in physics. The availability of low cost lasers in recent years allows us to perform the double slit experiment rather easily in class. Your professor shines a green laser (560 nm) on a double slit with a separation of 0.108 mm. The diffraction pattern shines on the classroom wall 3.0 m away. Calculate the fringe separation between the third order and central fringe.
Answer:
y = 4.666 10⁻² m
Explanation:
The constructive interference experiment for the double slit
d sin sin θ = m λ
Let's use trigonometry to find a sine relationship.
Tan θ = y / L
tan θ = sin θ/ cos θ
in these experiments the angles are very small
tan θ = sin θ
sin θ = y / L
[tex]d \frac{y}{L}[/tex] = m λ
y = [tex]\frac{ m \lambda \ L}{d}[/tex]
we replace the values
y = 3 560 10⁻⁹ 3.0 / 0.108 10⁻³
y = 4.666 10⁻² m
A cart moves with negligible friction or air resistance along a roller coaster track. The cart starts from rest at the top of a hill of unknown height. It then goes down that first hill and up another circularly shaped hill of height 10 meters and radius 15 meters. The ride is designed so that the cart just barely loses contact with the track at the top of the second hill (10 meters above ground level). What is the height of the starting hill relative to ground
Answer:
hinit = 17.5 m
Explanation:
Assuming no friction present, the mechanical energy must be conserved, which means that at any point of the trajectory, the sum of the gravitational potential energy and the kinetic energy must keep the same.At the top of the hill, since it starts from rest, all the energy must be potential, and we can express it as follows:[tex]E_{o} = U_{o} = m*g*h_{init} (1)[/tex]
When the car arrives to the top of the second hill, as we know that it is lower than the first one, the energy of the car, must be part gravitational potential energy, and part kinetic energy.We can express this final energy as follows:[tex]E_{f} = U_{f} + K_{f} = m*g* h_{2} + \frac{1}{2} *m*v_{f} ^{2} (2)[/tex]
In order to find hinit, we need to make (1) equal to (2), and solve for it.In (2) we have the value of h₂ (10 m), but we still need the value of the speed at the top of the second hill, vf.Now, when the car is at the top of the hill, there are two forces acting on it, in opposite directions: the normal force (upward) and the weight (downward).We know also that there is a force that keeps the car along the circular track, which is the centripetal force.This force is just the net downward force acting on the car (it's vertical at the top), and is just the difference between the weight and the normal force.If the cart just barely loses contact with the track at the top of the second hill, this means that at that point the normal force becomes zero.So, the centripetal force must be equal to the weight.The centripetal force can be expressed as follows:[tex]F_{c} = m*\frac{v_{f} ^{2}}{R} (3)[/tex]
We have just said that (3) must be equal to the weight:[tex]F_{c} = m*\frac{v_{f} ^{2}}{R} = m*g (4)[/tex]
Simplifying, and rearranging, we can solve for vf², as follows:[tex]v_{f}^{2} = R*g (5)[/tex]
Replacing (5) in (2), simplifying and rearranging in (1) and (2) we finally have:[tex]h_{init} = h_{2} + \frac{1}{2} R = 10m + 7.5 m = 17.5 m (6)[/tex]
Need a little help here, ASAP please. The subject is simple science, not physics.
Why do we use copper wiring?
Explanation:
The lower the level of resistivity the more electrical conductivity a metal has. Copper has low resistivity, and therefore is an excellent conductor. Copper is also less oxidative than other metals
I need help with science please, ill give brianlist’s :
Question 1 :The size of a plant cell may change depending upon the amount of water it receives.
True
False
________________________________
Question 2: Chloroplasts are a category of organelles found in the cells of green plants.
True
False
_______________________________
Question 3: Photosynthesis in plants produces water and carbon dioxide.
True
False
Answer:
true , true, and I'm not sure about the last one!
Explanation:
Direction of Wave Travel
С
Which letter
correctly
identifies the
wavelength of
this wave?
А
B
A. A
B. B
C. C
Answer:
I THINK it's A but I'm not completely sure