Answer:
Explanation:
net force on the skier = mg sin 39 - μ mg cos39
mg ( sin39 - μ cos39 )
= 73 x 9.8 ( .629 - .116)
= 367 N
impulse = net force x time = change in momentum .
= 367 x 5 = 1835 kg m /s
velocity of the skier after 5 s = 1835 / 73
= 25.13 m /s
b )
net force becomes zero
mg ( sin39 - μ cos39 ) = 0
μ = tan39
= .81
c )
net force becomes zero , so he will continue to go ahead with constant speed of 25.13 m /s
so he will have speed of 25.13 m /s after 5 s .
How is thermal energy transferred during conduction?
Answer:
Conduction occurs when a substance is heated, particles will gain more energy, and vibrate more. These molecules then bump into nearby particles and transfer some of their energy to them. This then continues and passes the energy from the hot end down to the colder end of the substance.
Explanation:
May I have brainliest please? :)
can the transfer of heat by convection occur in solids ?why?
Answer:
cannot
Explanation:
because convection occurs to difference in densities between particles and there is a movement of particles during convection ( gases and liquids ) , in solids , atoms are very tightly packed and cannot move
Which of the following is an example of convection?
A
heating an iron pipe by placing it into a fire
B
warming one's hands by rubbing them together
C
melting an ice cube in a microwave
D
heating water to a rolling boil
Answer:
D. Heating water to a rolling boil
A car starts from rest and is moving at 60.0 m/s after 7.50 s. What is the car's average acceleration?
Help!!!
Answer:
[tex]{ \boxed{ \bold{ \sf{Acceleration \: ( \: a) = 8 \: m/ {s \: }^{2} }}}}[/tex]
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♨ Question :
A car starts from rest and is moving at 60.0 m/s after 7.50 s. What is the car's average acceleration ?♨ [tex] \underbrace{ \sf{Required \: Answer : }}[/tex]
☄ Given :
Initial velocity ( u ) = 0 Final velocity ( v ) = 60.0 m/sTime ( t ) = 7.50 s☄ To find :
Acceleration ( a )✒ We know ,
[tex] \boxed{ \underline{ \bold{ \sf{Acceleration \: ( \: a) = \frac{Final velocity ( v ) - Initial velocity ( u)}{t} }}}}[/tex]
Substitute the values and solve for a.
➛ [tex] \sf{a = \frac{60.0 - 0}{7.50}} [/tex]
➛ [tex] \sf{a = \frac{60.0}{7.50}} [/tex]
➛ [tex] \boxed{ \boxed{ \sf{a = 8 \: m/ {s \: }^{2} }}}[/tex]
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✑ Additional Info :
When a certain object comes in motion from rest , in the case , initial velocity ( u ) = 0When a moving object comes in rest , in the case , final velocity ( v ) = 0If the object is moving with uniform velocity , in the case , u = v.If any object is thrown vertically upwards in the case , a = -gWhen an object is falling from certain height , in the case , final velocity at maximum height ( v ) = 0.Hope I helped!
Have a wonderful time ツ
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if i roll pieces of allium foil in a ball what property of aluminium foil changes as a result of my action
Answer:
Malleability
Explanation:
The ability to roll aluminum foil in a ball is the property of metal called malleability.
Metallic bonds in metals makes it possible for them to take different shape without losing internal cohesion. Metals are malleable and they posses a wide range of physical properties. A malleable metal can be beaten into sheets and molded into many shapes.Temperature is a measure of how much the atoms in a substance are moving. Why is a substance hotter in the gas
state than in the liquid state?
Atoms can move to change a liquid's shape.
O Atoms can be compressed when in the gas state.
Atoms move more freely in the gas state.
Atoms move in the gas state but not the liquid state.
Answer:
Atoms move more freely in the gas state.
Explanation:
e2020
A substance is hotter in the gas state than in the liquid state because atoms move more freely in the gas state.
What is temperature?The term "temperature" describes how hot or cold a body is. It is, specifically, a method of calculating the kinetic energy of the particles that make up an item. When particles move more quickly, the temperature rises, and vice versa.
Nearly every aspect of our daily lives and all scientific fields, from physics to geology, are significantly influenced by temperature.
The average kinetic energy of the particles in an object is measured by its temperature. The velocity of these particles likewise increases as the temperature rises.
As atoms move more freely in the gas state, a substance is hotter in the gas state than in the liquid state.
Learn more about temperature here:
https://brainly.com/question/11464844
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A piece of rocky debris in space has a semi major axis of 45.0 AU. What is its orbital period?
Complete Question
Planet D has a semi-major axis = 60 AU and an orbital period of 18.164 days. A piece of rocky debris in space has a semi major axis of 45.0 AU. What is its orbital period?
Answer:
The value is [tex]T_R = 11.8 \ days[/tex]
Explanation:
From the question we are told that
The semi - major axis of the rocky debris [tex]a_R = 45.0\ AU[/tex]
The semi - major axis of Planet D is [tex]a_D = 60 \ AU[/tex]
The orbital period of planet D is [tex]T_D = 18.164 \ days[/tex]
Generally from Kepler third law
[tex]T \ \ \alpha \ \ a^{\frac{3}{2} }[/tex]
Here T is the orbital period while a is the semi major axis
So
[tex]\frac{T_D}{T_R} = \frac{a^{\frac{3}{2} }}{a_R^{\frac{3}{2} }}[/tex]
=> [tex]T_R = T_D * [\frac{a_R}{a_D} ]^{\frac{3}{2} }[/tex]
=> [tex]T_R = 18.164 * [\frac{ 45}{60} ]^{\frac{3}{2} }[/tex]
=> [tex]T_R = 11.8 \ days[/tex]
The orbital period of the rocky debris in space is 12 days.
From Kepler's law, we know that the square of the period of a planet in years is equal to the cube of its mean distance from the sun in astronomical units (AU).
Mathematically;
[tex]T^2 = r^3[/tex]
Now, we have the mean distance as 45.0 AU, we need to obtain its period.
semi major axis of debris rR= 45.0 AU
semi major axis of planet D rD = 60 AU
Period of planet D TD = 18.164 days
Period of debris TR = ?
[tex]\frac{TR^2}{TD^2} = \frac{rR^3}{rD^3}[/tex]
[tex]\frac{rR^3}{rD^3} * TD^2[/tex]
[tex]TR^2 = 45^3/60^3 * 18.164^2[/tex]
TR = 12 days
Missing parts:
Planet D has a semi-major axis = 60 AU and an orbital period of 18.164 days. A piece of rocky debris in space has a semi major axis of 45.0 AU. What is its orbital period?
Learn more: https://brainly.com/question/14281129
If the net force on an object is zero, what would be its acceleration
Radio waves travel at a speed of 300,000,000 m/s.
KQFC broadcasts radio waves at a frequency of 97,900,000 Hertz.
What is the wavelength of KQFC’s radio wave?
Answer:
3.06 mExplanation:
The wavelength of KQFC’s radio wave can be found by using the formula
[tex] \lambda = \frac{v}{f} \\ [/tex]
v is the velocity
f is the frequency
Fromthe question we have
[tex] \lambda = \frac{300000000}{97900000} = \frac{3000}{979} \\ = 3.064351...[/tex]
We have the final answer as
3.06 mHope this helps you
Sitting at the top of a steep hill on a roller coaster (not moving), is an example of:
11. In order for an object moving at 10 m/s to have a kinetic energy of 1800
Joules, the object must have a mass in the range of *
O 0-10 kg
O 20-30 kg
30-40 kg
Answer:
20 to 30
Explanation:
20 to 30 is the correct answer
6. A 2000 kg spacecraft is located 9.2x10 m from the center of the earth. The mass of the earth
is 6.0x1024 kg. What is the force of gravity acting on the spacecraft?
The answer is -i, trust me.
You push a 10 n object 10 meters. How much work was done on the object
which answer is right? thanks if u help me! :)
Answer:7.5 x 10* 14
Explanation:
Answer: I believe the answer is 7.5 x 10^(14)Hz or 7.5E14Hz
Explanation: the formula for frequency is speed of the wave divided by the wavelength
f= c/wavelength
f- frequency
c-speed
(3 x 10^(8)) x (400 x 10^(-9))= 750,000,000,000,000 or 7.5E14 or 7.5 x10^(14)
What is the power of an electric with a current of 0.5 A and a voltage of 120 V ? The formula for power is P =IV
Answer:
60Watts
Explanation:
Given parameters:
Current = 0.5A
Voltage = 120V
Unknown
Power = ?
Solution:
The power in the electric circuit is the product of current and voltage;
P = IV
Insert the given parameters and solve;
P = 0.5 x 120
P = 60Watts
The longer the wavelength, the lower the frequency, and the lower the energy. Lesson 4.07 True False
1. What mass can be lifted by the hydraulic press if it is known that the are:
of the small piston is 48cm and that of the large piston is 1440cm, and
the force acting on the small piston can be as large as 1000N. (use g =
10m/s)
C. 3000kg
B. 30kg
D. 30,000kg
A. 300kg
Answer:
Answer: C. 3000kg
Explanation:
Hydraulic Jack
It's a device that is used to lift heavy loads by applying force via a hydraulic cylinder.
Since the internal pressure on the liquid of the jack is constant, the following relation applies:
[tex]\displaystyle \frac{F_1}{A_1}=\frac{F_2}{A_2}[/tex]
Where
F1 = Force applied in one end of the jack
A1 = Area of the cylinder of the same end
F2 = Force applied in the other end of the jack
A2 = Area of the cylinder of the other end
If we assume the force is being applied on side 1, then the force on side 2 is calculated by solving for F2:
[tex]\displaystyle F_2=\frac{F_1.A_2}{A_1}[/tex]
We have F1=1000N, A1= 48~cm^2, A2= 1440~cm^2, thus:
[tex]\displaystyle F_2=\frac{1000.1440}{48}[/tex]
[tex]F_2 = 30000 ~N[/tex]
Since we need to know the mass that can be lifted by that force, we use the formula:
W = m.g
Where W is the weight of the mass and g= 10~m/s^2. Since the weight is equal to the force exerted by the jack:
[tex]\displaystyle m=\frac{W}{g}=\frac{30000}{10}[/tex]
m = 3000 Kg
Answer: C. 3000kg
A skateboarder skates down a ramp for 3 seconds. If his initial velocity was 0.8 m/s and · his final velocity was 7 m/s, what was his acceleration?
Answer:
The acceleration of the skateboarder is 2.067 m/s²
Explanation:
Given;
initial velocity of the skateboarder, u = 0.8 m/s
final velocity of the skateboarder, v = 7 m/s
time of motion, t = 3 s
The acceleration of the skateboarder is given as;
[tex]a = \frac{v-u}{t}\\\\a = \frac{7-0.8}{3}\\\\a = 2.067 \ m/s^2[/tex]
Therefore, the acceleration of the skateboarder is 2.067 m/s²
which of the following is a pure substance?
a. solution
b. compound
c. homogeneous mixture
Answer:
B.
Explanation:
In a scientific context, “pure” denotes a single type of material. Ostensibly, compounds contain more than one type of material. Yet both compounds and elements are considered pure substances. Pure compounds are created when elements combine permanently, forming one substance.
What is Newton's 3rd law of motion?
A.When objects collide they exert a force to balance both out
B.For every action there is no reaction
C.If an object exerts a force on a second object the second exerts an equal force in the opposite direction
D.Force is applied when there are two opposite objects
Answer:
Explanation:
B
C. If an object exerts a force on a second object, the second exerts an equal force in the opposite direction.
Explanation:
I took the test lol
could someone look this one over for me and tell me the answer. i would app it.
Answer:
3m/s^2
Explanation:
newton's 2nd law F=MA
f is given as 30 and m is 10
plug into the equation and find a is 3 (30/10)
Which factor has the greatest effect on the strength of an electromagnet?
A. The position of the ammeter in the circuit
B. The number of coils of wire around the core
C. The type of insulation that covers the wire
D. The distance between the battery and the electromagnet
B. The number of coils of wire around the core
Answer:
B.
Explanation:
The number of coils of wire around the core
Taylor Swift weighing 794 N gets on an elevator. The elevator uses 313 W of power to lift the person 22.0 m. How much time did the elevator take to lift the Taylor?
Answer:
55.80s
Explanation:
Power is calculated using the expression
Power = Work done/Time
Workdone= Force ×distance
Workdone = 794×22
Work done = 17468Joules
From the power formula
Time = Workdone/Power
Time = 17468/313
Time = 55.80seconds
The elevator takes 55.80seconds to life the Taylor
Assuming temperature is constant, what is the new volume when a 100.0 cm3 container at 120.0 kPa is expanded until the pressure is 60.0 kPa?
Answer:
200cm³
Explanation:
Given parameters;
Initial volume = 100cm³
Initial pressure = 120kPa
Final pressure = 60kPa
Unknown:
Final volume = ?
Solution:
The temperature is constant, we apply Boyle's law to solve this problem.
Boyle's states that "the volume of fixed mass of a gas varies inversely as the pressure changes, if the temperature is constant".
Mathematically;
P₁V₁ = P₂V₂
P and V are the pressure and volume
1 and 2 are the initial and final values;
Now insert the parameters and solve;
120 x 100 = 60 x V₂
V₂ = 200cm³
Unas niñas en el receso estaban jugando a derramar flatulencias en un frasco de forma cilíndrica, cuyo radio tenía 5" y una altura de 7 in, el gas se mantenía constante a una presión de 540 mm de Hg. Si se baja la presión a 320 mm de Hg, ¿Cuál será el volumen que posea la flatulencia?
Answer:
Los gases siempre se adaptaran al volumen del contenedor en el que estén.
Entonces, si baja la presión del gas, la temperatura se mantendrá constante, lo que implica que tiene que aumentar la temperatura, pues para un gas ideal tenemos:
P*V = n*k*T
donde si el frasco esta cerrado, tenemos que n, k y V son constantes, entonces:
P = (n*k/V)*T
P = constante*T
(Notar que si el frasco no estuviera cerrado, entonces el numero n variaría de forma incontrolable, y este problema no se podría resolver de forma sencilla)
Entonces, si la presión baja, también baja la temperatura, pero el volumen se mantendrá constante, eso es lo importante.
Como el volumen se mantiene constante, el volumen que tomara el gas va a ser igual al volumen del frasco, sabemos que el volumen de un cilindro es:
V = (pi*r^2*h)
donde:
r = radio
pi = 3.14
h = altura.
en este caso, r = 5'' = 5 in
h = 7 in
Entonces el volumen sera:
V = 3.14*(5in)^2*7in = 549.5 in^2
m part one if you get stuck!
1 point
A ball is thrown. It has an initial speed of 5 m/s. It stops 5 seconds later. What was the
acceleration of the ball? *
-5 m/s^2
1 m/s^2
5 m/s^2
25 m/s^2
O -1 m/s^2
Answer:
-1m/s^2
Explanation:
Answer:
the answer is 0-1m/S2 ok
A box is initially at rest on a horizontal, frictionless table. If a force of 10
Newton acts on the box for 3 seconds, what is the momentum of the
box at the end of the 3 second interval?
Answer: 18
Explanation:
i think
Answer: 30
Explanation: ck-12 momentum and impulse
Question 25
1 pts
A bowling ball rolls off the edge of a giants table at 15 m/s horizontally. If it takes 2 s
for the ball to hit the ground, what is the height of the table?
O 80 m
40 m
50 m
O 10 m
20 m
kk
A 5000kg freight car moving at 2 m/s East collides with a 10,000kg freight car at rest. Upon collision, they got stuck and moved with same velocity. Find their final velocity after collision
Answer:
A
Explanation:
A graph titled Position versus time for with horizontal axis time (seconds) and vertical axis position (meters). The line runs in 3 straight segments from 0 seconds 0 meters to 4 seconds 12 meters to 6 seconds 12 meters to 12 seconds 0 meters.
Use the graph to determine the velocity between 6 and 12 seconds.
m/s
A -2
B -1
C 0
D 1
E 2
What was the velocity over the entire trip?
A -2
B -1
C 0
D 1
E 2
m/s
Answer:
The first one is 3 m/s
The second one is 2 m/s
Explanation:
Answer:
first one is
-2
Second one
0
Explanation:
trust me