Answers
Related Questions
A 4 kg object moving to the left collides with and sticks to a 3 kg object moving to the right. Which of the following is true of the motion of the combined objects immediately after the collision?
a. They must be moving to the left.
b. They must be moving to the right.
c. They must be at rest.
d. The motion cannot be determined without knowing the speeds of the objects before the collision.
Answers
Answer:
D. The motion cannot be determined without knowing the speeds of the objects before the collision.
Explanation:
This question is tricky! We know the object moving to the left has a greater mass than the one moving to the right. We'd assume they would move to the left because the leftwards object has a greater mass, right?
Not. So. Fast.
We can solve for the objects' final velocity using the formula for momentum, m₁v₁ + m₂v₂ = (m₁ + m₂)v .
Now here's where the trap is sprung: we don't think about the equation. This shows that the final velocity of the objects and the direction depends on both the mass of the objects and their initial velocity.
Basically, what if the 3 kg object is moving at 1 m/s and the 4 kg object is moving at –0.5 m/s? The objects would move to the right after the collision!
Do we know the velocity of these objects? No, right?
That means we can't determine the direction of their motion unless we know their initial, pre-collision velocity. This question is tricky because we look at the 4 kg vs. 3 kg and automatically assume the 4 kg object would dictate the direction of motion. That's not true. It depends on velocity as well.
I hope this helps you! Have a great day!
If a car is traveling at an average speed of 20 m/s, how long will it take to travel 500 meters?
A. 0.04 seconds
B. 25 seconds
C. 520 seconds
D. 10,000 seconds
Answers
Answer:
B. 25 seconds
Explanation:
500÷20=25
B.25 seconds
A 10kg toy truck has a 5kg toy car at rest. If the toy truck was moving at 3 m/s before the collision and carries that car with it, what is the
Final velocity of the car and truck.
A. 15 m/ s
B. 30 m/ s
C 2 m/ s
D. 18 m/ sc free
Answers
Answer:
[tex]v_f=2\:\mathrm{m/s}[/tex]
Explanation:
From the Law of Conservation of Momentum, momentum is conserved. Therefore, we can set up the following equation:
[tex]m_1v_1+m_2v_1=m_fv_f[/tex]
Since the 5kg toy car was initially and rest, [tex]m_2v_2=0[/tex].
Therefore, plugging in our values, we have:
[tex]10\cdot 3=(10+5)v_f,\\v_f=\frac{30}{15},\\v_f=\fbox{$2\:\mathrm{m/s}$}[/tex].
Answer:
Let m1 = mass of big toy car=10kg
m2= mass of small toy car= 5kg
U1= initial velocity of big toy car= 3m/s
U2= initial velocity of small toy car=0
Since the big toy car moved the small one after the collision, their final velocity will be the same.
m1u1 + m2u2= (m1+m2)v
10(3)+(5)(0)=(10+5)v
30=15v
Divide both sides by 15
V=2
The final velocity is 2m/s
Explanation:
An object of mass 5kg travels in the positive direction with a speed of 1ms1ms. The object collides with a second object that exerts an average net force over an interval of time such that the 5kg object comes to rest. Which of the following best predicts the change in momentum for the 5kg object?
a. The change in momentum is in the negative direction.
b. The change in momentum is in the positive direction.
c. The change in momentum is zero.
d. The direction of the change in momentum cannot be determined without knowing the value of the average force and time in which the force is exerted.
Answers
Answer:
Explanation:
The change in momentum is in the negative direction.
which changes will increase the rate of reaction during combustion
Answers
Answer:
reducing temperature of the surrounding
Explanation:
combustion reactions are exothermic so they give off heat. reducing the temperature of the surrounding will enable more efficient energy transfer
An electric heater draws a steady 15.0A on a 120-V
line. How much power does it require and how
much does it cost per month (31days) if it operates
2.0 h per day and the electric company charges 15.5
cents per kWh?
Answers
Answer:
1. 1800 W
2. $ 17.3
Explanation:
From the question given above, the following data were obtained:
Current (I) = 15 A
Voltage (V) = 120 V
Time (t) = 20 h per day
Duration = 31 days
Cost = 15.5 cents per kWh
1. Determination of the power.
Current (I) = 15 A
Voltage (V) = 120 V
Power (P) =?
P = IV
P = 15 × 120
P = 1800 W
Thus, 1800 W of power is required.
2. Determination of the cost per month (31 days).
We'll begin by converting 1800 W to KW.
1000 W = 1 KW
Therefore,
1800 W = 1800 W × 1 KW / 1000 W
1800 W = 1.8 KW
Next, we shall determine the energy consumption for 31 days. This can be obtained as follow:
Power (P) = 1.8 KW
Time (t) = 2 h per day
Time (t) for 31 days = 2 × 31 = 62 h
Energy (E) =?
E = Pt
E = 1.8 × 62
E = 111.6 KWh
Finally, we shall determine the cost of consumption. This can be obtained as follow:
1 KWh = 15.5 cents
Therefore,
111.6 KWh = 111.6 KWh × 15.5 cents / 1 KWh
111.6 KWh = 1729.8 cents
Converting 1729.8 cents to dollar, we have:
100 cents = $ 1
Therefore,
1729.8 cents = 1729.8 cents × $ 1 / 100 cents
1729.8 cents = $ 17.3
Thus, it will cost $ 17.3 per month to run the electric heater.
The amount of power it requires is 180 Watt, and the cost per month to operate the electric heater for 2.0 h is 5.58 cent
To calculate the electric power required by the electric heater, we use the formula below.
⇒ Formula:
P = Vi................ Equation 1⇒ Where:
P = PowerV = Voltagei = currentFrom the question,
⇒ Given:
V = 120 VI = 15.0 A⇒ Substitute these values into equation 1
P = 120(1.5)P = 180 Watt.
For the cost of running the electric heater per month, if it operates 2.0 h per day. We use the relation below
C = Pt×C'/1000............... Equation 2⇒ Where:
C = The cost per month to operate the electric heater for 2.0ht = timeC' = Cost per kWh charge by the electric company.From the question,
⇒ Given:
C' = 15.5 cent per kWh t = 2.0 hP = 180 Watt⇒ Substitute these values into equation 2
C = 180(15.5)(2)/1000C = 5.58 cent.Hence, The amount of power it requires is 180 Watt, and the cost per month to operate the electric heater for 2.0h is 5.58 cent
Learn more about electric power here: https://brainly.com/question/16641884
What is the instantaneous velocity of a freely falling object 11 s after it is released from a position of rest
Answers
Answer:
v= -107.8 m/s
Explanation:
Since the object is in free fall, this means that is moving at an accceleration equal to the one due to gravity.Since it starts at rest, we can apply the definition of acceleration, rearranging terms as follows:[tex]v_{f} = v_{o} + a*t = a*t = -g*t = 9.8m/s2*11s = -107.8 m/s (1)[/tex]
(Assuming as positive the upward direction)Describe the effect of the amplitude on the velocity of the pulse!???
Answers
Answer:
Amplitude increases with decreasing velocity.
Explanation:
At the same time, an increase in attention takes place
I NEED HELP ASAP PLEASE!
Study the scenario.
Boiling water is poured into a Styrofoam cup and a metal cup. You pick up and hold the metal cup and the Styrofoam cup. The metal cup burns your fingers, but you can hold the Styrofoam cup without experiencing any pain.
The difference in the rate at which these two materials transfer thermal energy throughout the cups is known as __________.
evaporation
electrical energy
thermal conductivity
condensation
Answers
Answer: thermal conductivity
The difference in the rate at which these two materials transfer thermal energy throughout the cups is known as thermal conductivity.
What is thermal conductivity?It is the rate where the heat is to be transferred from conduction via the cross section area of the unit with respect to the material at the time when the temperature should be gradient and existed with the perpendicular to the area.
Also, in this, two material is to be transferred via the thermal energy with the help of cups.
Learn more about energy here: https://brainly.com/question/17447827
_____________________health is how you feel and how you react to situations bases on how you feel.
Group of answer choices
Mental
Physical
Emotional
Social
Answers
Answer: Emotional
Explanation:
Answer:
Physical
Explanation:
I love going going for a jog or a run so does my dog
what do scientists call a substance that forms during a chemical reaction
Answers
Answer:
A chemical reaction is a process in which one or more substances, also called reactants, are converted to one or more different substances, known as products.
Answer:
the answer is reactants i guess
Show that the speed of a moving particle over a time interval is constant if and only if its velocity and acceleration vectors are perpendicular over the time interval.
Answers
Answer:
[tex]|v|(t)=\sqrt{v_{x}^{2}(t)+v_{y}^{2}(t)+v_{z}^{2}(t)}=C[/tex]
[tex]2v(t)\cdot \frac{dv(t)}{dt}=0[/tex]
[tex]v(t)\cdot a(t)=0[/tex]
Explanation:
Let's start with the definition of a constant velocity.
If the velocity magnitude, in three dimensions, is a constant value (C) we have a constant velocity, which means.
[tex]|v|(t)=\sqrt{v_{x}^{2}(t)+v_{y}^{2}(t)+v_{z}^{2}(t)}=C[/tex]
Now, we know that the dot product between v(t) and v(t) is the |v|².
[tex]v(t)\cdot v(t)=|v|^{2}(t)[/tex]
If we take the derivative whit respect to time in both sides of this equation we will have:
[tex]\frac{d}{dt}(v(t)\cdot v(t))=\frac{d}{dt}|v|^{2}(t)[/tex]
We apply the product rule on the left side and the right side will zero because the derivative of a constant is 0.
[tex]\frac{dv(t)}{dt}\cdot v(t)+v(t)\cdot \frac{dv(t)}{dt}=0[/tex]
[tex]2v(t)\cdot \frac{dv(t)}{dt}=0[/tex]
We know that dv(t)/dt = a(t) (using the acceleration definiton)
Therefore, we conclude:
[tex]v(t)\cdot \frac{dv(t)}{dt}=0[/tex]
[tex]v(t)\cdot a(t)=0[/tex]
If the dot product is 0, it means that v(t) and a(t) are orthogonal.
I hope it helps you!
In 1800, Herschel wondered if the different colors of the rainbow were equal in brightness and heat. He used a prism to separate sunlight into it's different colors and thermometers to measure how much "heat energy" was included with each color. He also measured how much "brightness" was associated with each color. He noticed a "brightness" peak at the middle of the spectrum. Red and violet had the least amount of brightness with a "peak" at green and yellow. But for "heat energy", violet had the least and the amount of heat climbed more and more and showed no sign of a "peak" .
His observations supported the idea that neither Brightness nor heat were evenly distributed between the different colors. Some colors had more brightness (green and yellow) and a different color had the most heat (red).
But this lead to a new question. Did the "heat" exist even where there was no visible light and did it peak at wavelengths less than red. He did another set of experiments and found this to be the case. He again used a prism to separate sunlight into the colors of the rainbow. These colors were cast on a sheet of paper and a thermometer could be moved from one color to the next to measure the amount of heat. But this time, he moved the thermometers beyond the red light and made measurements on the paper where there was no visible light. He found the maximum amount of heat at wavelengths longer visible red light.
When Herschel selected where to place his thermometer and then measure the temperature, which variable was the Independent variable.
Question options:
A. The time of day
B. The month of the year
C. the temperature rise
D. the placement of the thermometer
Answers
Answer:
D.
Explanation:
im guessing.
PLEASEEEEEE HELPPPPPPP
Define resistance and discuss how it affects current.
Answers
Answer:
Resistance is the opposing of the flow of current through a conductor.
Waves in the ocean are tearing apart the shoreline. Which of the following two Earth Systems are interacting with each other.
Answers
Answer:
the Indian Ocean on 26 December 2004. This event claimed 227,898 dead and missing from 14 countries. The difference in mortality rates between these tsunamis reflects, in part, the benefits of understanding how tsunami waves are generated and move, and educating citizens to make scientifically
sound and potentially life-saving decisions.
A tsunami is a series of rapidly propagating, shallow-water ocean waves that develops when a submarine earthquake, landslide, or volcanic eruption displaces a large volume of water. Powerful earthquakes, with magnitudes of 9 or greater, caused both the 2004 and 2011 tsunamis. The earthquakes resulted from the movement of large tectonic plates. The 11 March 2011 earthquake occurred at 32 km (20
mi.) deep in Earth’s crust about 130 km (81 mi.) east of the city of Sendai. This location is on the boundary between two tectonic plates—the Pacific plate to the east and North American plate to the west. This
boundary fractured, releasing energy that was transmitted through the rocks and elevated portions of the
ocean floor. This drastic movement transmitted energy to the overlying ocean water, which generated
tsunami waves that radiated outward. The waves washed over the nearby coastlines and were felt around
the globe within hours (Figure 1.1).
Explanation:
Answer:
I believe Geosphere (lithosphere) and Hydrosphere
Explanation:
I hope it's right if not please notify me.
3. As the mass of an object increases, the force of gravity
Answers
Answer:
As the mass of an object increases, the force of gravity increases as well.
Explanation:
Objects with more mass have more gravity. They work together.
Two balls of unequal mass are hung from two springs that are not identical. The springs stretch the same distance as the two systems reach equilibrium. Then both springs are compressed and released. Which one oscillates faster?
a) The spring with the heavier ball,
b) Springs oscillate with the same frequency,
c) The spring with the light ball.
Answers
Answer:
b) Springs oscillate with the same frequency,
Explanation:
expression for frequency of vibration of mass hanging from a spring is given as follows
f = [tex]\frac{1}{2\pi} \times \sqrt{\frac{k}{m} }[/tex]
k is force constant of spring and m is mass vibrating .
In the present case, if mass stretches the spring by x and remains balanced
mg = k x
[tex]\frac{k}{m} =\frac{g}{x}[/tex]
g and x are same for both cases
[tex]\frac{k}{m}[/tex] will also be same for both cases .
Hence frequency of vibration will also be same for both the balls .
Why can ultraviolet waves be dangerous
Answers
Answer:
They can cause sunburn. Exposure to UV rays can cause premature aging of the skin and signs of sun damage such as wrinkles, leathery skin, liver spots, actinic keratosis, and solar elastosis. UV rays can also cause eye problems.
Explanation:
10) A soccer player kicks a soccer ball (m = 0.42 kg) accelerating from rest to 32.5m/s in 0.21s. Determine the force that sends soccer ball towards the goal.
G
U
E
S
S
Formula
11) Small rockets are fired to make small adjustments in the speed of a satellite. A certain small rocket can change the velocity of a 72,000kg satellite from 0m/s to 0.63m/s in 1296s. What force is exerted by the rocket on the satellite?
G
U
E
S
S
Formula
please I need help I don't understand it and I had to deliver it yesterday helpp:(
Answers
Explanation:
(10) Mass of a soccer player, m = 0.42 kg
Initial speed, u = 0
Final speed, v = 32.5 m/s
Time, t = 0.21 s
We need to find the force that sends soccer ball towards the goal.
Force, F = ma
[tex]F=\dfrac{m(v-u)}{t}\\\\F=\dfrac{0.42 \times (32.5-0)}{0.21}\\\\F=65\ N[/tex]
So, 65 N of force soccer ball sends towards the goal.
(11) Mass of the satellite, m = 72,000 kg
Initial speed, u = 0 m/s
Final speed, v = 0.63 m/s
Time, t = 1296 s
We need to find the force is exerted by the rocket on the satellite.
Force, F = ma
[tex]F=\dfrac{m(v-u)}{t}\\\\F=\dfrac{72,000\times (0.63-0)}{1296}\\\\F=35\ N[/tex]
So, 35 N of the force is exerted by the rocket on the satellite.
Hence, this is the required solution.
A car is traveling at speed of 18.6m/s and entering a 12m wide intersection when the light has 0.582seconds More Time remain yellow.
a) what does the acceleration of the car needed to be so that its infront is out of the intersection when the light turns red?
Answers
Answer:
6.94 m/s²
Explanation:
Given that:
Initial Velocity (u) = 18.6 m/s
Time, t = 0.582
S, distance = 12 m
S = ut + 0.5at²
12 = (18.6 * 0.582) + 0.5(a)(0.582²)
12 = 10.8252 + 0.169362a
12 - 10.8252 = 0.169362a
1.1748 = 0.169362a
a = 1.1748 / 0.169362
a = 6.9366209
a = 6.94 m/s²
Hence, acceliofbthe car should be 6.94 m/s²
PLEASSEE HELP MEEE WITHH THESEEE
Forty-five cm are equivalent to how many m? State your answer using Scientific Notation.
a
45 x 10^-2 m
b
4.5 x 10^-2 m
c
.45 x 10^-2 m
d
0.45 x10^-2 m
The radius of the earth is 6378 km. What is the diameter of the earth in meters? Use scientific notation to state your answer.
a
6378 x 10^3 m
b
.6378 x 10^3 m
c
6.378 x 10^6 m
d
6.378 x 10^3 m
In an experiment, you find the mass of a cart to be 250 grams. What is the mass of the cart in kilograms?
a
2.5 x 10^3 kg
b
2.50 x 10^3 kg
c
2.50 x 10^-3 kg
d
2.5 x10^-3 kg
Answers
Answer:
Q1: (a)
[tex]1cm \: = 10 {}^{ - 2}m[/tex]
so
[tex]45 \times {10}^{ - 2} m[/tex]
Q2:
[tex]1km = 10 {}^{3} m \\ 6378km \times {10}^{ 3} [/tex]
this is the radius in meter
diameter = 2r
in this i don't know which choice is the right answer
Q3:
[tex]1gram = \: {10}^{ - 3} kg[/tex]
so
[tex]250 \times {10}^{ - 3} = 2.5 \times {10}^{ - 1} kg[/tex]
again there is no correct answer
To understand and apply the formula τ=Iα to rigid objects rotating about a fixed axis. To find the acceleration a of a particle of mass m, we use Newton's second law: F net=ma , where F net is the net force acting on the particle.To find the angular acceleration α of a rigid object rotating about a fixed axis, we can use a similar formula: τnet=Iα, where τnet=∑τ is the net torque acting on the object and I is its moment of inertia.
Part A:
Assume that the mass of the swing bar, is negligible. Find the magnitude of the angular acceleration α of the seesaw.
Express your answer in terms of some or all of the quantities m1, m2, l, as well as the acceleration due to gravity g.
Part B:
Now consider a similar situation, except that now the swing bar itself has mass mbar.Find the magnitude of the angular acceleration α of the seesaw.
Express your answer in terms of some or all of the quantities m1, m2, mbar, l, as well as the acceleration due to gravity g.
Answers
Answer:
Hello your question is incomplete attached below is the missing part of the question
In this problem, you will practice applying this formula to several situations involving angular acceleration. In all of these situations, two objects of masses m1 and m2 are attached to a seesaw. The seesaw is made of a bar that has length l and is pivoted so that it is free to rotate in the vertical plane without friction. Assume that the pivot is attached tot he center of the bar.
You are to find the angular acceleration of the seesaw when it is set in motion from the horizontal position. In all cases, assume that m1>m2.I
answer : part A = 2*[(M1 - M2)/(M1 + M2)]*g/L
part A = attached below
Explanation:
Part A :
Assuming that mass of swing is negligible
α = T/I
where ; T = torque, I = inertia,
hence T = L/2*9*(M1 - M2)
also; I = [tex]M1*(L/2)^2 + M2*(L/2)^2[/tex]= ( M1 + M2) * (L/2)^2
Finally the magnitude of the angular acceleration α
α = 2*[(M1 - M2)/(M1 + M2)]*g/L
Part B attached below
. Which of the statement below about the magnetic
properties of iron and steel is correct?
A. Both iron and steel are equally magnetized and
demagnetized
B. Iron is more easilymagnetized and demagnetized
than steel.
C. Steel is more easily magnetized and demagnetized
than iron
D. Iron is more easily magnetized than steel but steel is
more easily demagnetized than iron.
Answers
Answer:
D. Iron is more easily magnetized than steel but steel is more easily demagnetized than iron.
In March 1999 the Mars Global Surveyor (GS) entered its final orbit about Mars, sending data back to Earth. Assume a circular orbit with a period of 7.08 × 103 s and orbital speed of 3.40 × 103 m/s . The mass of the GS is 930 kg and the radius of Mars is 3.43 × 106 m. Calculate the mass of Mars.
Answers
Answer: [tex]5.944\times 10^{23}\ kg[/tex]
Explanation:
Given
Time period [tex]T=7.08\times 10^3\ s[/tex]
Orbital speed [tex]v=3.40\times 10^3\ m/s[/tex]
mass of GS [tex]m_{GS}=930\ kg[/tex]
Radius of Mars [tex]r=3.43\times 10^6\ m[/tex]
Consider the mass of mars is M
Here, Gravitational pull will provide the centripetal force
[tex]F_G=F_c[/tex]
[tex]\dfrac{GMm_{GS}}{r^2}=\dfrac{m_{GS}v^2}{r}\\M=\dfrac{v^2\cdot r}{G}\\M=\dfrac{(3.43\times 10^3)^2\cdot 3.43\times 10^6}{6.67\times 10^{-11}}[/tex]
[tex]M=5.944\times 10^{23}\ kg[/tex]
In March 1999 the Mars Global Surveyor (GS) entered its final orbit on Mars, sending data back to Earth. The mass of Mars is approximately 6.419 × 10²³ kg.
Kepler's Third Law states that the square of the orbital period (T) is proportional to the cube of the semi-major axis (a) of the orbit:
T² = (4π² / GM) × a³
In a circular orbit, the semi-major axis is equal to the radius of the orbit (r).
Given:
Orbital period (T) = 7.08 × 10³ s
Orbital speed (v) = 3.40 × 10³ m/s
Mass of GS (m) = 930 kg
Radius of Mars (r) = 3.43 × 10⁶ m
The orbital speed (v) is related to the radius (r) and the gravitational constant (G) by:
v = √(GM / r)
v² = GM / r
G = (v² × r) / M
T² = (4π² / [(v² × r) / M]) × r³
T² = (4π² × M × r²) / v²
M = (T² × v²) / (4π² × r²)
M = ( (7.08 × 10³)² × (3.40 × 10³)² ) / (4π² × (3.43 × 10⁶)²)
M = 6.419 × 10²³ kg
Therefore, the mass of Mars is approximately 6.419 × 10²³ kg.
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The force of gravity acting on an object is directed through this
center of gravity and toward the center of the
Answers
Answer:
Earth.
Explanation:
Center of gravity can be defined as the specific point where all of the weight of an object is concentrated.
Generally, all the objects found around the world all have a center of gravity.
When an object is balanced so that a displacement lowers its center of gravity, the object is said to be in stable equilibrium.
Hence, the force of gravity acting on an object is directed through this center of gravity and toward the center of the earth.
Weight can be defined as the force acting on a body or an object as a result of gravity.
Mathematically, weight is given by the formula;
[tex] Weight, W = mg [/tex]
Where;
m is the mass of an object.
g is acceleration due to gravity.
A ball has a velocity of 11 m/s and a momentum of 47 kgm/s, what is its mass? Show
your given, required, and solutions.
Answers
Explanation:
p=m x v
to find the mass:
m= p/v
=47/11
=4.27 kg
Assuming no friction, how does the initial gravitational potential energy of
the marble on a downward slope compare to the final kinetic energy?
a) they are the same
b) the initial gravitational potential energy is greater than the final kinetic energy
c) the initial gravitational potential energy is less then the final kinetic energy
Answers
Answer:
a) They are the same.
Explanation:
Assuming no friction, there should be no energy transfer and thus the Law of Conservation of Energy says:
[tex]PE=KE,\\mgh=\frac{1}{2}mv^2[/tex]
These types of problems also disregard any air resistance the surface of the object may cause. Therefore, no energy is transferred and from the Law of Conservation of Energy, [tex]100\%[/tex] of energy is preserved.
I NEED HELP ASAPPPP PLEASE
Answers
The main idea of this paragraph is:
a. Boots is my dog.
b. Boots can sit.
c. Boots is very smart.
d. Most dogs can't dance.
Answers
A truck pushes a mound of dirt 5 meters with a force of 75 newtons. How much
work has been done?
Answers
Answer:
[tex]375\:\mathrm{N}[/tex]
Explanation:
Work is given by the equation [tex]W=F\Delta x[/tex]. Plugging in given values, we get:
[tex]W=75\cdot 5=\fbox{$ 375\:\mathrm{N}$}[/tex].