Help please!

3. A 75 kg linebacker moving at 6 m/s is running towards an 80 kg tackle moving 4 m/s. If they collide and stick together, how fast will they be moving after the collision?

5. A 6 kg bowling ball and a 4 kg bowling ball are rolled toward each other. The 6 kg ball is initially moving at 5.1 m/s and the 4 kg ball is moving in the opposite direction at 1.3 m/s. If the 6 kg ball slows to 1.5 m/s, what is the final speed of the 4 kg ball?

Answers

Answer 1

3. The sum of the players' momenta is equal to the momentum of the players when they're stuck together:

(75 kg) (6 m/s) + (80 kg) (-4 m/s) = (75 kg + 80 kg) v

where v is the velocity of the combined players. Solve for v :

450 kg•m/s - 320 kg•m/s = (155 kg) v

v = (130 kg•m/s) / (155 kg)

v ≈ 0.84 m/s

4. The total momentum of the bowling balls prior to collision is conserved and is the same after their collision, so that

(6 kg) (5.1 m/s) + (4 kg) (-1.3 m/s) = (6 kg) (1.5 m/s) + (4 kg) v

where v is the new velocity of the 4-kg ball. Solve for v :

30.6 kg•m/s - 5.2 kg•m/s = 9 kg•m/s + (4 kg) v

v = (16.4 kg•m/s) / (4 kg)

v = 4.1 m/s


Related Questions

I keep people warm I come in many different colors, styles, and materials. many people use me when they sit on a couch

Answers

Answer:

a seat

Explanation:

The phrase “seat value” is used in the hospitality and bar sectors to describe how much money each seat or square foot of customer area must generate to justify its existence.

What is the use of seat by the people?

An area to sit is a seat. The phrase may also refer to headquarters in a more general meaning as well as extra elements such a back, armrest, and head restraint.

Being in the centre allows you to benefit from both the advantages of both front and back seating while balancing out their extremes. While you're still close enough to be paying careful attention to the lecture, the middle rows will relieve you of the pressure and expectations of the front.

By remaining seated, students help avoid physical altercations. There is more time spent on task when pupils are seated.

Environmental psychology, which gives people the impression that they have some degree of influence over their daily lives, is the driving force behind all of this behavior.

Therefore, seat used by people.

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A 66 kg student stands on a very light, rigid board that rests on a bathroom scale at each end as shown in (Figure 1).

Answers

The reading on the scale is equal to the weight of the student which is 646.8 N.

The given parameters;

mass of the student, m = 66 kg

The reading on the scale is determined by applying Newton's second law of motion as follows;

[tex]R = ma+ mg\\\\R = m(a + g)\\\\R = m(0 + g)\\\\R = mg[/tex]

The student is at rest and not accelerating, a =0

[tex]R = 66 \times 9.8\\\\R = 646.8 \ N[/tex]

Thus, the reading on the scale is equal to the weight of the student which is 646.8 N.

The complete question is below:

A 66 kg student stands on a very light, rigid board that rests on a bathroom scale at each end as shown in (Figure 1). what is the reading on the scale?

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A loaded truck collides with a car causing huge damage to the car. Which of the following is true about the collision? *

A. The force on the truck is greater than the force on the car
B. The force on the car is greater than the force on the truck
C. The force on the truck is the same in magnitude as the force on the car
D. During the collision the truck makes greater displacement than the car
E. During the collision the truck has greater acceleration than the car

Answers

The force on the truck is the same in magnitude as the force on the car.

The impulse experienced by an object during collision is directly proportional to the applied force and time of collision of the objects.

J = Ft

where;

J is the impulse experienced by the objectt is the time

The increase in the force applied to an object causes an increase in the impulse experienced by the object.

Also, according to Newton's third law of motion, the force exerted on the loaded truck and the car are equal in magnitude but opposite in direction.

Thus, we can conclude that, the force on the truck is the same in magnitude as the force on the car.

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Now you need to put handles on your cookware! You have five different options, including metals and nonmetals such as wood. Based on specific heat, which material would be the best choice? the material with the smallest specific heat the material with the greatest specific heat the material whose specific heat is farthest from the specific heat of the metal pan the material whose specific heat is closest to the specific heat of the metal pan.

Answers

Answer: B the material with the greatest specific heat

Explanation:

Just did the assignment

Answer:

B. The material with the greatest specific heat

Explanation:

A blue line with 5 orange tick marks then one red tick mark then 4 orange tick marks. The number zero is above the red tick mark. Assume each tick mark represents 1 cm. Calculate the total displacement if a toy car starts at 0, moves 5 cm to the left, then 8 cm to the right, and then 3 cm to the left. The car moves cm, so there is no displacement.

Answers

The total displacement of the toy car at the given positions is 0.

The given parameters;

First displacement of the car, = 5 cm leftSecond displacement of the car, = 8 cm rightThird displacement of the car, = 3 cm to the left

The total displacement of the car is calculated as follows;

Let the left direction be "negative direction"Let the right direction be "positive direction"

[tex]\Delta x = - \ 5\ cm \ + \ 8 \ cm \ - \ 3 \ cm \\\\\Delta x = 0[/tex]

Thus, the total displacement of the toy car at the given positions is 0.

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Answer:0

Explanation:

A vertical spring stretches 9.6 cm when a 1.3 kg block is hung from its end. (a) Calculate the spring constant. This block is then displaced an additional 5.0 cm downward and released from rest. Find the (b) period, (c) freque

Answers

Answer:

F = - K x

a) K = 1.3 kg * 9.8 m/s^2 / .096 m = 133 kg/sec^2

b)  ω = (K/m)^1/2     angular frequency of SHM

ω = (133 / 1.3)^1/2 = 10.1 / sec

f = 2 π ω = 6.28 * 10.1 / sec = 63.5 / sec

P = 1/f = .0157 sec

Two 3.0g bullets are fired with speeds of 40.0 m/s
and 80.0 m/s, respectively. What are their kinetic
energies? Which bullet has more kinetic energy? What is the ratio of their kinetic energies?

Answers

Two 3.0g bullets are fired with speeds of 40.0 m/s and 80.0 m/s, respectively. Mass of the 1st bullet (m1) = 3 g = 0.003 KgMass of the 2nd bullet (m2) = 3 g = 0.003 KgVelocity of the 1st bullet (v1) = 40 m/sVelocity of the 2nd bullet (v2) = 80 m/sWe know, kinetic energy of a body

[tex] = \sf \frac{1}{2} m {v}^{2} [/tex]

Kinetic energy of the 1st bullet [tex] \sf = \frac{1}{2} \times m1 \times {(v1)}^{2} \\ \sf= \frac{1}{2} \times 0.003 \times {(40)}^{2}J \\ \sf = \frac{1}{2} \times 0.003 \times 1600J \\ \sf = 2.4J[/tex]Kinetic energy of the 2nd bullet [tex] \sf = \frac{1}{2} \times m2 \times {(v2)}^{2} \\ \sf= \frac{1}{2} \times 0.003 \times {(80)}^{2}J \\ \sf = \frac{1}{2} \times 0.003 \times 6400J \\ \sf = 9.6J[/tex] So, the 2nd bullet which has greater velocity has more kinetic energy.Therefore, the ratio of their kinetic energies

[tex] \sf = \frac{2.4J}{9.6J} \\ \sf= \frac{24}{96} = \frac{1}{4} \\ \sf = 1 : 4[/tex]

Answer:

The kinetic energies of the bullets are 2.4 J and 9.6 J.

The bullet having greater velocity has more kinetic energy.

The ratio of their kinetic energies is 1 : 4.

Hope you could get an idea from here

Doubt clarification - use comment section.

The kinetic energy of the two bullets are 2.4 J and 9.6 J respectively.

The ratio of the kinetic energy of the bullets is 1:4.

What is kinetic energy?

The kinetic energy of an object is the energy possessed by the object due to its motion.

The kinetic energy of the two bullets is calculated as follows;

[tex]K.E_1 = \frac{1}{2} \times 0.003 \times 40^2 = 2.4 \ J\\\\K.E_2 = \frac{1}{2} \times 0.003 \times 80^2 = 9.6 \ J[/tex]

Ratio of the kinetic energy of the bullets is calculated as follows;

[tex]K.E_1 : K.E_2 = 2.4: 9.6 \ = \ 1: 4[/tex]

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1 If you measured the distance travelled by a snail in
inches and the time it took in minutes, what would
be the units of its speed?

Answers

The answer is m/s hope it helps

Is mechanical energy the result of both kinetic and potential energy?

Answers

Answer:

Yes

Explanation:

Because putting them together would make a type of energy making the answer yes

The answer is: Yes, mechanical energy can be both kinetic and potential energy.

Explanation:

The mechanical energy of an object can be the result of its motion (i.e., kinetic energy) and/or the result of its stored energy of position (i.e., potential energy).

The total amount of mechanical energy is merely the sum of the potential energy and the kinetic energy. This sum is simply referred to as the total mechanical energy.

Is the image formed by a plane mirror always real?

True or false?​

Answers

this statement is false

GUYS COULD SOMEONE PLEASE HELP ME?
PLEASE ASAP

Write a summary of how the eye works:

Answers

Answer:

Eye function renders you the sense of sight. They convert light into electrical signals. Afterwards, the brain deciphers these electrical signals into images. Properly working healthy eyes are able to perform the following functions.

Explanation:

3. Suppose Earth orbited a star whose mass was double the mass of the sun. If the radius of Earth's orbit remained
the same as it is now, then compared with gravitational force between Earth and the sun, the gravitational force
between Earth and the star would be -
A. half as much
B. the same
C. two times as much
D. four times as much

Answers

Answer:

F1 = G M m / R^2       current force on earth

F2 = G M * 2 m / R^2     force if mass were doubled

F2 / F1 = 2         the force would be twice as large

The gravitational force between two objects not only depends on the mass but also the distance between them. If the distance to the star is same as to sun, then by doubling mass force also doubles. Thus option C is correct.

What is universal law of gravitation?

Gravitational force is the attractive force by which an object attracts other objects into its centre of mass. We are all standing in the ground because of the gravitational pull by earth.

The gravitational force between two objects of mass M1 and M2 at a distance r is written as follows:

g = G M1 M2/ r ² . where, G is gravitational constant.

As per this relation, gravitational force is directly proportional to the mass and inversely proportional to the square of the distance.

If the star has a distance from earth equal to the distance between sun and earth, but its mass is double the mass of sun, then the gravitational force will be two times compared with the sun.

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When the mass of the cylinder increased by a factor of 3, from 1. 0 kg to 3. 0 kg, what happened to the cylindera's gravitational potential energy? It decreased by a factor of 3. It decreased by a factor of 2. It increased by a factor of 2. It increased by a factor of 3.

Answers

The mass of the cylinder increased by a factor of 3, the  gravitational potential energy increases by a factor of 3.

The given parameters:

Initial mass of the cylinder, m₁ = 1.0 kgFinal mass of the cylinder, m₂ = 3.0 kg

The gravitational potential energy of an object is calculated as follows;

P.E = mgh

where;

m is the mass

g is acceleration due to gravity

h is the height of the cylinder

when the mass = 1 kg

P.E = 1 x g x h

P.E = gh

when the mass = 3 kg

P.E = 3 x gh

P.E = 3gh

Thus, when the mass of the cylinder increased by a factor of 3, the  gravitational potential energy increases by a factor of 3.

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Compare the amount of kinetic energy of particles in each state of matter- solid, liquid, gas

Answers

Answer:

gas moves around the most so it would have the most kinetic energy and solids would have the least as they only vibrate a tiny bit(not visible to the naked eye)

Galois drove 60.0 kilometers due west in 5.00 hours and then drove 43.0 kilometers due north in 3.00 hours.
(a) How far did he travel?
(b) What was his average speed?
(c) What was his displacement?
(d) What was his average velocity?

Answers

Answer:

Explanation:

See the attachment for the details.  A right triangle is formed to find the hypotenuse of the two legs consisting of the actual driving distances and times.  The hypotenuse gives the vector information for the displacement at the end of 8 hours of driving.  

The individual driving times and distances are summed to provide:

(a) How far did he travel?

103 km

(b) What was his average speed?

12.88 km/h

(c) What was his displacement?

73.82 km

(d) What was his average velocity?

9.228 km/h

An 50 kg student runs and jumps onto a 25 kg tire swing, which is initially at rest, and rides the swing up into the air. The swing (and the student) then rises a vertical distance of 1.5 m. What was the initial speed, in m/s of the swing? Remember the acceleration due to gravity near Earth's surface, g = 9.81 m/s^2

A. 29 m/s

B. 5.4 m/s

C. 1.7 m/s

D. 15. m/s

E. 3.8 m/s


Will mark brainliest

Answers

Answer:

Option B, 5.4m/s

Explanation:

Using the formula v² = u ² - 2gh

v = 0(final velocity is zero at maximum height), u = ?, g = 9.81m/s², h = 1.5m

0² = u² - 2×9.81×1.5

0 = u² - 29.43

29.43 = u²

u = √29.43

= 5.42m/s

What do scientists theorize about the origins of the Moon? Choose the most accepted explanation.

Answers

Answer:

What is most widely accepted today is a the giant-impact theory. It proposes that the Moon formed during a collision between the Earth and another small planet, about the size of Mars. The debris from this impact collected in an orbit around Earth to form the Moon.

yvonne van gennip of the netherlands ice skated 10.0 km with an average speed of 10.8 m/s. suppose vang ennip crosses the finish line at her average speed and takes a huge boquet of flowers handed to her by a fan. as a result her speed drops t o10.01 m/s. if van gennip’s mass is 63.0 kg what is the mass of the boquet?

Answers

By conservation of momentum, we will find that the mass is 4.97 kg.

So in the original system, we have two objects, the bouquet of flowers of mass M that is not moving and Yvonne, which has a mass of 63 kg and a speed of 10.8 m/s.

Then the total momentum of this system is:

P = (63kg)*(10.8m/s) + M*(0 m/s) = 680.4 kg*m/s.

Remember the conservation of momentum, thus, the final momentum must be equal to the above one.

In the final situation, Yvonne and the bouquet move together with a speed of 10.01 m/s,

Then the final momentum is:

P' = (63kg + M)*(10.01 m/s)

And that must be equal to the initial momentum, then we have the equation:

(63kg + M)*(10.01 m/s) = 680.4 kg*m/s.

630.63kg*m/s + M*10.01 m/s = 680.4 kg*m/s.

M*10.01 m/s = 680.4 kg*m/s - 630.63kg*m/s = 49.77 kg*m/s

M = (49.77 kg*m/s)/(10.01 m/s) = 4.97 kg

So the mass of the bouquet is 4.97 kg

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what is momentum?
what is period of an oscillating body?
what is friction?

Answers

Answer:

Explanation:

Momentum is the quantity of motion of a moving body, measured as a product of its mass and velocity.

The period of an oscillating body is the smallest interval of time in which a system undergoing oscillation returns to the state it was in at a time arbitrarily chosen as the beginning of the oscillation.

Friction is a force between two surfaces that are sliding, or trying to slide, across each other.  Friction always slows a moving object down. The amount of friction depends on the materials from which the two surfaces are made. The rougher the surface, the more friction is produced.

A car traveling at 100 km/hr strikes and unfortunate bug and splatters it.the net force of impact is

Answers

Answer:

it's zero

Explanation:

it is there is your answer

13. What are some ways that you can conserve energy?

Answers

Answer:

Adjust your day-to-day behaviors.

Replace your light bulbs.

Use smart power strips.

Install a programmable thermostat.

Use energy efficient appliances.

Reduce water heating expenses.

Install energy efficient windows.

Upgrade your HVAC system.

Turn Off Lights and Electronics When You Aren't Using Them. ...

Replace Traditional Light Bulbs with LEDs. ...

Get a Smart Thermostat. ...

Ensure Your Home is Properly Insulated. ...

Put Decorative Lights on a Timer. ...

Identify and Unplug Energy Vampires. ...

Reduce Appliance Use. ...

Use Less Hot Water.

what are the ending materials produced from cell respiration

Answers

Carbon dioxide and water :) hope this helped!

Answer:

The products of cellular respiration are carbon dioxide and water

Explanation:

Where in an equation for photosynthesis does glucose belong? on the left, because it is a product on the left, because it is a reactant on the right, because it is a product on the right, because it is a reactant

Answers

Answer: The answer is on the right, because it is a product.

Explanation: During photosynthesis, light energy converts carbon dioxide and water (the reactants) into glucose and oxygen (the products).

Glucose belongs to the right side in photosynthesis equation because it is a product on the right.

What is Photosynthesis?Photosynthesis is the conversion of light energy into chemical energy by green plants and other organisms. Light energy is collected and utilized by green plants during photosynthesis to transform water, carbon dioxide, and minerals into oxygen and energy-rich organic molecules Glucose.photosynthesis equation can be written as

6CO2 + 6H2O → C6H12O6 + 6O2.

Carbon dioxide + Water → Glucose + oxygen

Hence, the correct option is C.

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Initial Velocity is 27.5 m/s. Time is 42 seconds. Final Velocity is 4.5 m/s. Solve for acceleration.

Answers

Answer:

-0.5476

Explanation:

a=(Vf-Vi)/t

a=(4.5-27.5)/42

a=-0.547619047

acceleration≈-0.5476

Find the area of the given figure

Answers

Answer:

77 sq.cm

Explanation:

Solution,

Trapezium

Perpendicular (P1)=8cm

Perpendicular(P2)=14cm

height(h)=7cm

Now,

We know that,

Area(A)= 1/2 ×h (P1+P2)

= 1/2 × 7cm (8cm+14cm)

= 1/2 × 7cm(22cm)

= 1/2 × 154 squarecm

=77 sq.cm

A bullet of mass M1 is fired towards a block of mass m2 initially at rest at the edge of a frictionless table of height h as in the figure. The initial speed of the bullet is vi . Consider two cases, a completely inelastic one and an elastic one,where the bullet bounces off the block. inelastic case elastic case a bullet inside no bullet inside A B A' B' What is the ratio of the flight time; i.e., tAB tA′B′ ?

Answers

The ratio of time of flight for inelastic collision to elastic collision is 1:2

The given parameters;

mass of the bullet, = m₁mass of the block, = m₂initial velocity of the bullet, = u₁initial velocity of the block, = u₂

Considering inelastic collision, the final velocity of the system is calculated as;

[tex]m_1u_1 + m_2u_2 = v(m_1 + m_2)\\\\m_1u_1 + 0 = v(m_1 + m_2)\\\\v= \frac{m_1u_1}{m_1 + m_2} \ -- (1)\\\\[/tex]

The time of motion of the system form top of the table is calculated as;

[tex]v = u + gt\\\\v = 0 + gt\\\\v = gt\\\\t= \frac{v}{g} \\\\t_A = \frac{m_1u_1}{g(m_1 + m_2)} \ \ ---(2)[/tex]

Considering elastic collision, the final velocity of the system is calculated as;

[tex]m_1u_1 + m_2 u_2 = m_1v_1 + m_2v_2\\\\m_1u_1 + 0 = m_1v_1 + m_2v_2\\\\m_1 u_1 = m_1v_1 + m_2v_2[/tex]

Apply one-directional velocity

[tex]u_1 + (-v_1) = u_2 + v_2\\\\u_1 -v_1 = 0 + v_2\\\\v_1 = v_2 -u_1[/tex]

Substitute the value of [tex]v_1[/tex] into the above equation;

[tex]m_1u_1 = m_1(v_2 - u_1) + m_2 v_2\\\\m_1u_1 = m_1v_2 -m_1u_1 + m_2v_2\\\\2m_1u_1 = m_1v_2 + m_2v_2\\\\2m_1u_1= v_2(m_1 + m_2)\\\\v_2 = \frac{2m_1u_1}{m_1+ m_2} \ --(3)[/tex]

where;

[tex]v_2[/tex] is the final velocity of the block after collision

Since the bullet bounces off, we assume that only the block fell to the ground from the table.

The time of motion of the block is calculated as follows;

[tex]v_2 = v_0 + gt\\\\v_2 = 0 + gt\\\\t = \frac{v_2}{g} \\\\t_B = \frac{v_2}{g} \\\\ t_B = \frac{2m_1u_1}{g(m_1 + m_2)} \ \ ---(4)[/tex]

The ratio of time of flight for inelastic collision to elastic collision is calculated as follows;

[tex]\frac{t_A}{t_B} = \frac{m_1u_1}{g(m_1 + m_2)} \times \frac{g(m_1 + m_2)}{2m_1u_1} \\\\\frac{t_A}{t_B} = \frac{1}{2} \\\\t_A:t_B = 1: 2[/tex]

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To overcome an object's inertia, it must be acted upon by __________. A. Gravity B. Energy C. Force D. Acceleration Please select the best answer from the choices provided. A B C D.

Answers

Taking into account the Newton's first Law, the correct answer is option C. To overcome an object's inertia, it must be acted upon by a force.

Newton's First Law, also called the Law of inertia, indicates that "Every body perseveres in its state of rest or of uniform rectilinear motion unless it is forced to change its state by forces impressed on it." This means that for a body to come out of its state of rest or of uniform rectilinear motion, it is necessary for a force to act on it.

In other words, it is not possible for a body to change its initial state (be it rest or motion) unless one or more forces intervene.

Finally, the correct answer is option C. To overcome an object's inertia, it must be acted upon by a force.

Learn more:

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Answer:

C) Force

Explanation:

Jeremiah rides his bicycle 4 miles in 30 minutes. If he maintains this rate, how far will he ride in 3 hours?

Answers

Answer:

24 miles.

Explanation:

3 hours=180 minutes

180÷30=6

6x4=24

How long will it take a projectile to hit the ground if it is launched at 4.2 m/s off a 12.6 m high platform?

Answers

Answer: 3

Explanation:

I think you are supposed to divided in those problems? I'm not sure but if you aren't then please let me know. The equation I did was:

12.6 / 4.2 = 3

Hope this helps!! :)

What should you do before inserting a wire into an outlet box?
A. Place a bushing inline.
B. Remove a foot of the outer covering.
C. Clean the terminals.
D. Strip at least three inches and re-twist the strands to retighten.

Answers

The first thing that you should do before inserting a wire into an outlet box is to remove a foot of the outer covering.

What is an outlet box?

The outlet box is sometimes called the junction box. It is from this point that  power is distributed to appliances in the home. Its main function is to protect against short circuits.

The first thing that you should do before inserting a wire into an outlet box is to remove a foot of the outer covering.

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