PHYSICS COLLEGE

A 110 kg ice hockey player skates at 3.0 m/s toward a railing at the edge of the ice and then stops himself by grasping the railing with his outstretched arms. During the stopping process, his center of mass moves 30 cm toward the railing. (a) What is the change in the kinetic energy of his center of mass during this process? (b) What average force must he exert on the railing?

Answers

Answer 1

Answer:

Answer:

(a). The change in the kinetic energy of his center of mass during this process is -495 J.

(b). The average force is 1650 N.

Explanation:

Given that,

Mass = 110 kg

Speed = 3.0 m/s

Distance = 30 cm

(a). We need to calculate the change in the kinetic energy of his center of mass during this process

Using formula of kinetic energy

$\Delta K.E=K.E_(2)-K.E_(1)$

$\Delta K.E=(1)/(2)mv_(f)^2-(1)/(2)mv_(i)^2$

Put the value into the formula

$\Delta K.E=(1)/(2)*110*0^2-(1)/(2)*110*(3.0)^2$

$\Delta K.E=-495\ J$

(b). We need to calculate the average force must he exert on the railing

Using work energy theorem

$W=\Delta K.E$

$Fd=\Delta K.E$

$F=(\Delta K.E)/(d)$

Put the value into the formula

$F=(-495)/(30*10^(-2))$

$F=-1650\ N$

The average force is 1650 N.

Hence, (a). The change in the kinetic energy of his center of mass during this process is -495 J.

(b). The average force is 1650 N.

Answer 2

Answer:

Answer

given,

mass of ice hockey player = 110 Kg

initial speed of the skate = 3 m/s

final speed of the skate = 0 m/s

distance of the center of mass, m = 30 cm = 0.3 m

a) Change in kinetic energy

$\Delta KE = (1)/(2)mv_f^2 - (1)/(2)mv_i^2$

$\Delta KE = (1)/(2)m(0)^2 - (1)/(2)* 110 * 3^2$

$\Delta KE = - 495\ J$

b) Average force must he exerted on the railing

using work energy theorem

W = Δ KE

F .d = -495

F x 0.3 = -495

F = -1650 N

the average force exerted on the railing is equal to 1650 N.

Related Questions

Your classmate’s mass is 63 kg and the table weighs 500 N. Calculate the normal force on the table by the floor. Show your work!
A basketball player jumps straight up for a ball. To do this, he lowers his body 0.250 m and then accelerates through this distance by forcefully straightening his legs. This player leaves the floor with a vertical velocity sufficient to carry him 0.960 m above the floor. (a) Calculate his velocity (in m/s) when he leaves the floor. 4.33 Correct: Your answer is correct. m/s (b) Calculate his acceleration (in m/s2) while he is straightening his legs. He goes from zero to the velocity found in part (a) in a distance of 0.250 m.
Question Part Points Submissions Used A car is stopped for a traffic signal. When the light turns green, the car accelerates, increasing its speed from 0 to 5.30 m/s in 0.812 s. (a) What is the magnitude of the linear impulse experienced by a 62.0-kg passenger in the car during the time the car accelerates? kg · m/s (b) What is the magnitude of the average total force experienced by a 62.0-kg passenger in the car during the time the car accelerates? N
A. With what speed must a ball be thrown vertically from ground level to rise to a maximum height of 45m?b. How long will it be in the air?
Write down the DE of motion of a particle moving under the influence of gravity and experiencing a resistive force. .

PLEASE HELP!!! Sophia says that if we add two electrons to oxygen in order to fill its valence shell, it’s expected charge would be +2. Is she correct? If not, explain the error in her thinking.

Answers

The error in her thinking is that oxygen has has six electrons and a negative charge is acquired by nitrogen when it gains two electrons.

Oxygen is a member of group 16. The elements in group 16 has six valence electrons. This means that they need an extra two electrons to complete their octet.

If an atom gains two electrons, it will have a charge of -2 and not +2, a positive charge means that the atom lost electrons. Nonmetals like oxygen do not loose electrons rather they gain electrons.

Learn more: brainly.com/question/14156701

A force of 140 140 newtons is required to hold a spring that has been stretched from its natural length of 40 cm to a length of 60 cm. Find the work done in stretching the spring from 60 cm to 65 cm. First, setup an integral and find a a, b b, and f ( x ) f(x) which would compute the amount of work done.

Answers

Answer:

The work done in stretching the spring is 0.875 J.

Explanation:

Given that,

Force = 140 N

Natural length = 60-40 = 20 cm

Stretch length of the spring = 65-60 = 5 cm

We need to calculate the spring constant

Using formula of Hooke's law

$F= kx$

$140=k*20*10^(-2)$

$k=(140)/(20*10^(-2))$

$k=700$

We need to calculate the work done

$W=\int_(a)^(b){kx}dx$

$=\int_(0)^(0.05){700x}dx$

On integration

$W=700*((x^2)/(2))_(0)^(0.05)$

$W=700*(((0.05)^2)/(2)-0)$

$W=0.875\ J$

Hence, The work done in stretching the spring is 0.875 J.

A rigid tank initially contains 3kg of carbon dioxide (CO2) at a pressure of 3bar.The tank is connected by a valve to a frictionless piston-cylinder assembly located vertically above, initially containing 0.5 m^3 of CO2. The piston area is 0.1 m^2. Initially the pressure of the CO2 in the piston-cylinder assembly is 2 bar. The ambient pressure and temperature are 1 bar and 290 K. Although the valveis closed, a small leak allows CO2 to flow slowly into the cylinder from the tank. Owing to heat transfer, the temperature of the CO2 throughout the tank and the piston-cylinder assembly stays constant at 290K. You can assume ideal gas behavior for CO2.Determine the following:

a. The total amount of energy transfer by work (kJ)
b. The total amount of energy transfer by heat (kJ)

Answers

Answer:

Part a: The total amount of energy transfer by the work done is 54.81 kJ.

Part b: The total amount of energy transfer by the heat is 54.81 kJ

Explanation:

Mass of Carbon Dioxide is given as m1=3 kg

Pressure is given as P1=3 bar =300 kPA

Volume is given as V1=0.5 m^3

Pressure in tank 2 is given as P2=2 bar=200 kPa

T=290 K

Now the Molecular weight of $CO_2$ is given as

M=44 kg/kmol

the gas constant is given as

$R=\frac{\bar{R}}{M}\nR=(8.314)/(44)\nR=0.189 kJ/kg.K$

Volume of the tank is given as

$V=(mRT)/(P_1)\nV=(3 * 0.189 * 290)/(300 )\nV=0.5481 m^3$

Final mass is given as

$m_2=(P_2V)/(RT)\nm_2=(200* 0.5481)/(0.189* 290)\nm_2=2 kg$

Mass of the CO2 moved to the cylinder

$m=m_1-m_3\nm=3-2=1 kg$

The initial mass in the cylinder is given as

$m_((cyl)_1)=(P_((cyl)_1)V_1)/(RT)\nm_((cyl)_1)=(200* 0.5)/(0.189 * 290)\nm_((cyl)_1)=1.82 kg$

The mass after the process is

$m_((cyl)_2)=m_((cyl)_1)+m\nm_((cyl)_2)=1.82+1\nm_((cyl)_2)=2.82\n$

Now the volume 2 of the cylinder is given as

$V_((cyl)_2)=(m_((cyl)_2)RT)/(P_2)\nm_((cyl)_2)=(2.82* 0.189* 290)/(200)\nm_((cyl)_1)=0.774 m^3$

Part a:

So the Work done is given as

$W=P(V_2-V_1)\nW=200(0.774-0.5)\nW=54.81 kJ$

The total amount of energy transfer by the work done is 54.81 kJ.

Part b:

The total energy transfer by heat is given as

$Q=\Delta U+W\nQ=0+W\nQ=54.81 kJ$

As the temperature is constant thus change in internal energy is 0.

The total amount of energy transfer by the heat is 54.81 kJ

Convert this measurement
664.2 km=____cm

Answers

(664.2 km) · (1,000 m/km) · (100 cm/m) =

(664.2 · 1,000 · 100) (km·m·cm/km·m) =

66,420,000 cm

For metric conversion, you can remember this acronym for help:

King Henry died unusually drinking chocolate milk. Which stand for:

Kilo - unit * 1000

Hecto - unit * 100

Deca - unit * 10

Unit - unit * 1

Deci - unit * $(1)/(10)$

Centi - unit * $(1)/(100)$

Milli - unit * $(1)/(100)$

Kilometers and centimeters are five places apart apart, so you move the decimal point in 664.2 to the right five times, which means 664.2 km = 66420000 cm.

To avoid confusion on which direction to move the decimal point, imagine two shapes on each end of a scale. On each end, there is one large shape and one small shape. There has to be one of each on either side for it to balance. For this problem, a kilometer is a larger unit than a centimeter, so this means that the blank space needs to have a number greater than 664.2, or else the scale won't balance. Hope this helped.

In the figure, determine the character of the collision. The masses of the blocks, and the velocities before and after are given. The collision is (Show your work-no work shown = ZERO POINTS) 1.8 m/s 0.2 m/s 0.6 m/s 1.4 m/s 4 kg 6 kg 4 kg 6 kg Before After A) perfectly elastic. B) partially inelastic. C) completely inelastic. D) characterized by an increase in kinetic energy E) not possible because momentum is not conserved.

Answers

When two bodies come into close touch with one another, a collision occurs. In this instance, the two bodies quickly exert forces on one another. The collision changes the energy and momentum of the bodies that are interacting.

Briefing

the system's initial kinetic energy, KEi, is equal to 0.5 * 4 * 1.8 2 plus 0.5 * 6 * 0.2 2 J.

KEi = 6.6 J

The system's ultimate kinetic energy, KEf

, following the collision is equal to 0.5 * 4 * 0.6 + 0.5 * 6 * 1.4 J.

KEf = 6.6 J

since KEi = KEf

Perfectly elastic is the collision

the appropriate response is A) completely elastic.

Visit: to learn more about absolutely elastic.

brainly.com/question/14450755

#SPJ4

If the solution described in the introduction is cooled to 0 ∘c, what mass of kno3 should crystallize? enter your answer numerically in grams.

Answers

14 g is the solubility per 100 g water, since it is difficult to read the graph.
Then, in 130 g H20 the solubility would be 14 g KNO3/100 g H2O x 130 g H2O = 18 g KNO3
The question asks how much crystallizes.
Initial 34.0 g minus 18.0 g still dissolved = 16.0 g crystallizes.

KNO3 of 10g will undergo crystallization at 0 °

Because the heavier the KNO3 mass will require a higher temperature in the dissolution process.

Further explanation

Potassium nitrate is a nitrate salt compound from potassium with the molecular formula KNO3. Potassium nitrate salt can be made by reacting potassium chloride with sodium nitrate. If the saturated solution each of the solution is mixed with each other, then it will form sodium chloride salt because NaCl in water is small, the salt will settle. By cooling the filtered filtrate KNO3 will undergo crystallization

This compound decomposes with oxygen evolution at 500 ° C according to the reaction equation:

2 NaNO3 (s) -> 2NaNO 2 (s) + O2 (g)

Crystallization is separation by forming crystals so that the mixture can be separated. A gaseous or liquid substance can cool or condense and form crystals because it undergoes a crystallization process. Crystals will also form from a solution that will be saturated with a certain solvent. The more the number of crystals, the better, because the less likely to be polluted by dirt.

Potassium Nitrate has a physical white powder that is easily soluble in water and odorless. Meanwhile, to analyze the structure and characteristics of Potassium Nitrate MM2 data processing is used in the Chemoffice 15.0 application. This data processing is used to determine the shape of compounds, types of bonds in molecular movement compounds and other parts that can not be observed directly by the eye without the aid of tools. And for the form of compounds in 2 dimensions and 3 dimensions used Chemdraw 15.0 and Chem3D 15.0 applications

Learn more

Potassium nitrate brainly.com/question/10847775

Crystallization brainly.com/question/2575925

Details

Grade: High School

Subject: Chemistry

Keyword: kno3, nitrate, crystallization

Other Questions

Two narrow slits separated by 1.5 mm are illuminated by 514 nm light. Find the distance between adjacent bright fringes on a screen 5.0 m from the slits. Express your answer in meters using two significant figures.

At what temperature will silver have a resistivity that is two times the resistivity of iron at room temperature? (Assume room temperature is 20° C.)

The electric field at a point 2.8 cm from a small object points toward the object with a strength of 180,000 N/C. What is the object's charge q? ( k = 1/4πε 0 = 8.99 × 10 9 N ∙ m 2/C 2)

The normal is a line perpendicular to the reflecting surface at the point of incidence.