A ball with a mass of 4 kg is dropped from a height of 20 m. What is the velocity of the ball just before it hits the ground? g = 10 m/s^2

The conservation of momentum in an elastic collision is conserved whereas in an inelastic collision it is conserved but kinetic energy is lost.

When an elastic collision occurs in an isolated system, the total momentum of the object system is conserved. Assuming no net external forces acting on the objects, the momentum of all objects before the collision equals the momentum of all objects after the collision.

An inelastic collision is a type of collision that occurs between two objects in which energy is lost. In an inelastic collision, momentum is conserved, but kinetic energy is not. Most collisions in everyday life are inelastic in nature.

Learn more about the conservation of momentum in

https://brainly.com/question/3920210

#SPJ4

The final speed of the astronaut at the space station is 0.36 m/s and the direction will be opposite to the direction of the tool kit thrown.

The mass of the astronaut = 80 kg

The mass of the tool kit = 15 kg

The speed of the space station = 1.25 m/s

The speed of the tool kit threw = 6 m/s

The final speed of the astronaut can be found using the conservation of momentum formula,

           [tex]\displaystyle m_{1}v_{f1} + m_{2}v_{f2} = m_{1}v_{i1} + m_{2}v_{i2}[/tex]

where m₁ is the mass of the astronaut

           m₂ is the mass of the tool kit

           [tex]\displaystyle v_{i1}[/tex] and [tex]\displaystyle v_{i2}[/tex] is the speed of the space station

           [tex]\displaystyle v_{f1}[/tex] is the speed of the astronaut after throwing the toolkit

Let us substitute the known values in the above equation, we get

              (80 x [tex]\displaystyle v_{f1}[/tex]) + (15 x 6) = (80 x 1.25) + (15 x 1.25)

                     (80 x [tex]\displaystyle v_{f1}[/tex]) + 90 = 100 + 18.75

                              80 x [tex]\displaystyle v_{f1}[/tex]   = 118.75 - 90

                                80 x [tex]\displaystyle v_{f1}[/tex] = 28.75

                                        [tex]\displaystyle v_{f1}[/tex] = 28.75 / 80

                                              = 0.36 m/s

Therefore, the final speed of the astronaut is 0.36 m/s

By newton's third law, for every action, there will be an equal and opposite reaction. Thus, the direction of the astronaut's direction will be against the direction of the tool kit thrown.

Learn more about the conservation of momentum in

https://brainly.com/question/2456421

#SPJ4

The force needed to bring a car to rest from a speed is 2,541 Newton.

The formula in non-uniform motion

v = u + at

v² = u² + 2ad

[tex]d = u \times t + \frac{1}{2} \times a \times t^2[/tex]

Because the final speed is km/h, we must convert it into m/s

v = 85.0 km/h

v = [tex]85.0 \times \frac{1 \: km}{1 \: hour}[/tex]

v = [tex]85.0 \times \frac{1,000 \: m}{3,600 \: s}[/tex]

v = [tex]\frac{850}{36}[/tex]

v = 23.6 m/s

Calculate the acceleration

v² = u² + 2ad

23.6² = 0² + (2×a×15)

556.96 = 230a

[tex]a = \frac{556.96}{230}[/tex]

a = 2.42 m/s

Formula to find the force F=ma

F = ma

F = 1,050×2.42

F = 2541 Newton

Learn more about Force here: https://brainly.com/question/11847879

#SPJ4

The number of elements pictured in the above image is 3 (option C).

Element are any one of the simplest chemical substances that cannot be decomposed in a chemical reaction or by any chemical means and made up of atoms all having the same number of protons.

There are about 118 chemical elements, each with its own type of atom. Everything in the universe contains the atoms of at least one or more elements. The periodic table lists all the known elements, grouping together those with similar properties.

According to this question, elements are represented by different colours. Each colour represents each element.

The three colours are as follows:

This means that there are three elements in the above image.

Learn more about elements at: https://brainly.com/question/14347616

#SPJ1

The speed of the child and sled at the bottom of the slope is 11 m/s.

Mechanical energy, is the sum of potential energy and kinetic energy. The principle of conservation of mechanical energy states that mechanical energy is constant if an isolated system is subjected to only conservative forces.

Combined mass (m) = 40 kg

Speed at top of slope (v) = 5 m/s

Height of slope (h) = 10 m

Entire range of the slope (d) = 100 m

Force of friction (F) = -20 N

Work done by friction (W) = F × d

= -20 × 100

= -2000 J

Kinetic energy (KE) of sled at the top of slope = ¹/₂ mv²

= ¹/₂ × 40 × 5²

= 500 J

Potential energy (PE) of sled at the top of slope = mgh

= 40 × 9.8 × 10

= 3920 J

Now, total energy (E) of sled/child system at the top of slope = KE + PE

= 500 + 3920

= 4420 J

So, the energy left at the bottom of slope:

4420 J - 2000 J

= 2420 J

Now this lost energy is converted into kinetic energy of the system:

KE = ¹/₂ mv²

2420 J = ¹/₂ × 40 × v²

v² = 121

v = 11 m/s

To know more about mechanical energy visit:

https://brainly.com/question/28928306

#SPJ4

We are given with a case of a moving shopping cart.

We are asked , how to increase the time, change the force.

For that, if we reduce the applied force in order to increase the time interval.

Generally, if we know the force applied and time taken, we can calculate the change in momentum.

As, Force, F = dP/dt

i.e. Rate of change of momentum w.r.t. time is Force.

So, dP = F.dt

Unit of Force is Newton, N in MKS (metre kilogram second) system.

Unit of Force is Dyne in CGS (centimetre gram second) system.

To know more about Force:

brainly.com/question/13191643

#SPJ4

Total distance travelled by the athlete is 37.03km as it is calculated by the expression of distance in terms of speed and time.

Velocity is the distance travelled by a moving body per unit time . Distance travelled is the speed unit time.here an athlete runs with velocity 12 km/hr in 55 min, 14 km/hr in next 22 min and 19 km/hr for the next 66 min.

              55min= 55/60hr  ,

              22min=22/60hr ,

              66 min= 66/60 hr.

        Distance= speed . time

       Putting these in the expression

    Total speed= 55/60 hr..12 km +22/60 hr. .14 km/hr  + 66/60hr . 19       km/hr.

            = 37.03 km

To learn more about Velocity please visit :

https://brainly.com/question/25749514

#SPJ4

There is a 40000 N/C downward electric field between the plates.

Potential difference between the plates V = 2000 V

Plates separation d = 5 cm = 0.05 m

power source E=V/d

Electric field E=40000 N/C downhill

The electric force per unit of charge is what is meant when we talk about an electric field. It is presumable that the field's direction matches the direction in which a successful test charge would feel force. The physical surroundings of a system of charged particles are also described. Electric fields are composed of electric charges and time-varying electric currents. The electromagnetic field, one of nature's four primary interactions, or forces, appears as both electric and magnetic fields.

In electrical technology, electric fields are used, and significant in many branches of physics. For instance, the attracting force in atomic physics and chemistry is the electric field.

Learn more about Electric field  here:

https://brainly.com/question/15800304

#SPJ4

With wavelengths of around 10-1000 m, radio waves used by cell phones to communicate with cell towers are far too big to be ionizing. In reality, WiFi runs at very specific frequencies, 2.4 GHz or 5 GHz, which correspond to wavelengths of 12 cm or 6 cm, respectively.

Since radiofrequency waves are electromagnetic fields rather than ionizing radiation like X-rays or gamma rays, they cannot ionize or destroy chemical bonds in living organisms.

The signal is transformed back into the data that was first sent by the transmitter when the radio waves reach a receiver. Your voice is sent through radio waves to the person you are contacting when you use a cell phone as a transmitter.

The primary means of communication between mobile phones and neighboring cell towers is through RF waves, an electromagnetic spectrum energy type.

learn more about  electromagnetic spectrum refer

https://brainly.com/question/13803241

#SPJ1

The magnitude of the student's resultant displacement is 50 m.

To find the magnitude of displacement we must make all the paths.

Look at the picture

d² = 40²+30²

d² = 1,600+900

d² = 2,500

[tex]d \:=\: \sqrt{2,500}[/tex]

d = 50 m

Learn more about Displacement here: https://brainly.com/question/28370322

#SPJ4

Answer:

As P is increased from mg(sinθ−μcosθ) to mg(sinθ+μcosθ) frictional force will change from mgcos ( upwards parallel to inclined plane) to 0 to mgcos (downwards parallel to inclined plane). Under the approximation of linear variation of P the correct option is A.

The animal with the lowest bar on that bar graph would be the mountain lion.

A bar graph is a visual representation of data that uses rectangular bars having lengths according to the values they represent. A bar graph, which can be shown horizontally or vertically, compares sets of data.

According to the question, mountain lions had the lowest bar on a bar graph since they have the smallest population 150 of all the species.

Bar graphs are a way of representing the numerical data sets of different aspects on a graph paper that allows easy calculations and conclusions.

On the graph sheets, the quantitative method is shown as bars, which show their values.

The answer to the query indicated that Mountain Lions would have the graph's lowest bar.

The picture provided below shows the plotted and associated bar graph again for the aforementioned query.

The vertical or y-axis represents the animal population, while the horizontal or x-axis shows the various species of animals.

Mountain lions are the species with the least amount of residents in the area.

Learn more about bar graphs at

https://brainly.com/question/8543469?referrer=searchResults

#SPJ4

The question is -

If the data below were put into a bar graph, which animal would have the lowest bar on the bar graph? Number of Individuals in a Rocky Mountain Forest Organism Population Mountain lions 150 Bobcats 300 Coyotes 10,000 Deer 25,000 mountain lions bobcats coyotes deer Mark this and return Save and Exit.

Answer: the answer is A

Explanation:i got it from a friend it was right

The graph that best represents the relationship between the velocity of an object thrown straight upward from the Earth's surface and the time that elapses while it is in the air is (option D)

Velocity is the directional speed of a moving object as an indicator of its rate of change in location as perceived from a certain frame of reference and measured by a specific time standard.

In other words, velocity is the primary indication of an object's location as well as its speed. It is defined as the distance traveled by an item in one unit of time. The displacement of an item in unit time is defined as velocity.

The equation that speaks to the velocity at a vertically upwards object that is accelerated against gravity and time is given as:

v = u + at; where

v = velocity

u = point from which the object starts to move

a is acceleration; and

t is time.

Learn more about velocity:
https://brainly.com/question/18084516
#SPJ1

Full Question:

See attached image

To reduce the uncertainty in the measurement of the period in oscillation.

A mechanical device that oscillates swings from side to side. A peg-and-slot can convert it into a rotary motion (rotating in a circle). The similar technique can be used to convert rotary motion to oscillating motion.

Sine and cosine functions can be used to describe the motion of a simple harmonic oscillating system where the restoring force is directly proportional to that of the displacement and acts in the direction opposite to that of displacement. One illustration is a weight fastened to a spring. The weight is in equilibrium when it is at rest. If the weight is reduced, the mass is subject to a net restoring force (potential energy)

To know more about  oscillation visit : https://brainly.com/question/29273618

#SPJ4

If the star radiates uniformly in all directions, the total power output of the star is 2.37 x 10²⁷ W.

The formula for the intensity of the light at a distance R from the source of light (which is star in this case) is given by,

I = P/A

I is the intensity,

P is the power,

A is the area.

We can write,

P = IA

Intensity is given to be 15.4 W/m².

A = πR²

Here, we will take the value of R is 7 x 10¹² m.

So,

A = π( 7 x 10¹²)²

Putting the values,

P = IA

P = 15.4 x π x ( 7 x 10¹²)²

P = 2.37 x 10²⁷ W.

The power output of the star is 2.37 x 10²⁷ W.

To know more about intensity of light, visit,

https://brainly.com/question/20877138

#SPJ4

a ) When they reach the ground, rock B has greater velocity.

b ) Both rocks have the same acceleration

c ) Rock A and Rock B arrives at the same time

According to law of conservation of energy,

1 / 2 m u² + m g hi = 1 / 2 m v² + m g hf

u = 0

hf = 0

m g hi = 1 / 2 m v²

v = √ ( 2 g / m ) √ hi

v ∝ √ hi

a ) hi of rock A will be higher because it reaches a certain height above the ground which will be considered as initial height for rock A. So, the final velocity of rock A is higher.

b ) Both the rock are affected by only the force of gravity. So they will have the same acceleration of 9.8 m / s²

c ) If air resistance is ignored,

s = u t + 1 / 2 at²

For an object that is dropped,

u = 0

a = g

s = at² / 2

t = √ ( 2 s / g )

It can clearly be seen that no matter what height an object might be dropped from, if air resistance is ignore they will fall at the same time.

Therefore,

a ) When they reach the ground, rock B has greater velocity.

b ) Both rocks have the same acceleration

c ) Rock A and Rock B arrives at the same time

To know more about law of conservation of energy

https://brainly.com/question/12050604

#SPJ1

The total amount of energy remains the same. It just changes from one form to another as the person swings back-and-forth. Statement (C) is true.

Energy is the ability to perform work in physics. It could exist in several different forms, such as potential, kinetic, thermal, electrical, chemical, radioactive, etc. Additionally, there is heat and work, which is energy being transferred from one body to another.

When Manuel was watching his younger siblings on the swing set; the motion of swinging is a kind  of simple harmonic motion where total energy remains conserved. But kinetic and potential energy are continuously exchanged in simple harmonic motion.

Potential energy is at its peak and kinetic energy is zero when you are farthest from the equilibrium point. The kinetic energy is at its peak and the potential energy is zero at the equilibrium point. The oscillating body's kinetic and potential energy values change at other points in its motion. So, the total amount of energy remains the same. It just changes from one form to another as the person swings back-and-forth.

To kind more about energy; refer the link:

https://brainly.com/question/1932868

#SPJ1

Distance between nodal planes is calculated to be 2.4m, when given frequency is 125MHz .

A radio transmitter is an electronic circuit that transforms electric power from a power source into a radio frequency alternating current to the antenna and then the antenna radiates the energy from this current as radio waves.

As we know that, F= c/λ

where c -->speed of light and λ --> wavelength

λ = 2L/n

where; L --> length and n -->nodes

Given frequency = 125 MHz

λ = c / F

= 3 * 10⁸/ 125 *10⁶

λ= 2.4

Hence, distance between nodal planes is 2.4m

To know mote about radio transmitter, refer

https://brainly.com/question/28342514

#SPJ4

A cylindrical resistor of radius 4.5 mm and length 2.0 cm is made of material that has a resistivity then current density J is  1.12 × [tex]10^{5}[/tex]

Since P = i^2 r = (J^2) (A^2) R

J = 1/A [tex]\sqrt{P/R}[/tex]

Current density (J)  = 1.12 × [tex]10^{5}[/tex]

A material's electrical resistivity, also known as specific electrical resistance or volume resistivity, is a key characteristic that quantifies how effectively it resists electric current. A substance that permits electric current to flow easily has a low resistance. The Greek letter is often used to signify resistivity (rho). Ohm-meters (m) are the metric unit for electrical resistivity.  For instance, the resistivity of a material is 1 m if it has sheet contacts on two of its opposing faces and has a 1 resistance between them.

Learn more about Current density here:

https://brainly.com/question/13958826

#SPJ4

The acceleration for the 40kg and 60 kg person will be 3 m / s² and - 2 m / s² respectively if the 60kg man pushes the 40kg woman with 120 N force.

F = m a

F = Force

m = Mass

a = Acceleration

For 40 kg woman,

m = 40 kg

F = 120 N

a = F / m

a = 120 / 40

a = 3 m / s²

For 60 kg man,

According to Newton's third law of motion, for every action there will be an equal and opposite reaction. So the 40 kg woman will push back with a force of - 120 N.

a = - 120 / 60

a = - 2 m / s²

The negative sign indicates negative direction.

Therefore, the acceleration for the 40kg and 60 kg person will be 3 m / s² and - 2 m / s² respectively

To know more about acceleration

https://brainly.com/question/12550364

#SPJ4

The ball's initial velocity  is  14 m/s

Since the equation of motion we referring to for  calculating  the initial velocity are :

s=ut+1/2at²  ....1

v²= u²+2as .... 2

where u and v are initial and final velocity, t is the time taken, a is the acceleration due to gravity and s is the distance or we can also  say the height .As we are given h₁ and  h₂ which are 2.45 m and  7.45 m and the time is taken, t which is  1.45 s, and at last we are having a = -9.8ms^-2

using the 2 equations, we get  

v₁= √(u²−2gh₁),

from equation 1, we get

h₂ =√(u₂−2gh₁t)−1/2gt₂

there the initial velocity will be:

u= √(((h₂+1/2gt²)/t)²+2gh1

 =√(((7.35+1/2*9.80*(1.45)^2)/1.45)^2+2×9.80×2.45)

 = 14

to know more about velocity refer to the  link  https://brainly.com/question/18084516?referrer=searchResults.

#SPJ4

The direction of net force at all points in the projectile's path is downwards towards the ground.

F = m a

F = Force

m = Mass

a = Acceleration

F ∝ a

The direction of net force is influenced by the direction of acceleration.

In a projectile motion, if the air resistance is considered negligible, there will be no acceleration in horizontal direction. Because, there will be no forces acting in horizontal direction. The only force acting on the projectile is the force of gravity. Gravity pulls the object downwards throughout its motion. So the direction of net force will be downwards at all points in the projectile's path.

Therefore, the direction of net force at all points in the projectile's path is downwards towards the ground.

To know more about projectile motion

https://brainly.com/question/11049671

#SPJ1

Using the concepts of gravitation, we find that it is true that tides are the periodic short term change in the height of the ocean surface at a particular place, generated by the long wavelength progressive waves that are caused by  interaction of gravitational force of the moon and sun.

Gravitational force is one of  basic forces of nature. It is a force that acts between two bodies and it is always attractive in the nature. Gravitational force is the force with which the objects are attracted to the centre of  earth. The motion of the planets and the moon are  governed by this force

Kepler’s first law All the planets will revolve around the sun in an elliptical orbit with the sun at one of the focus.

Hence, tides are the periodic short term change in the height of  the ocean surface at a particular place, generated by the long wavelength progressive waves that are caused by  interaction of gravitational force of the moon and sun is true.

To know more about gravitation, visit here:

https://brainly.com/question/3009841

#SPJ4

Answer:

To say we have a 12.0-V battery implies that its terminals have a 12.0-V likely contrast. At the point when such a battery moves charge, it puts the charge through an expected distinction of 12.0 V, and the charge is given an adjustment of potential energy equivalent to Δ U = q Δ V .

six cells

There are six cells to a 12 volt lead corrosive battery. A battery cell's greatest capacity to convey current (amps).

A 6 cell lithium particle pack has an ostensible voltage of 21.6V to 22.2V and a most extreme charge voltage of 25.2 volts

Explanation:

The moment of inertia of the boxer's forearm will be 0.525kg.[tex]m^{2}[/tex]

In physics, it means quantitative measure of the rotational inertia of the body. As an example, the opposition that the body exhibits to having its speed of rotation about an axis altered by the application of a torque (turning force). The axis may be internal or external and may or may not be fixed.

From the question given, the triceps muscle in the back of the upper arm extends the forearm of a professional boxer when he extends his arm,
Torque generated due to this force is,

τ = F * r
τ = torque is generated

F = force exerted = 2903n
r = the radius of the lever arm = 2.35cm = 0.0235m

Now let's use the torque formula
τ = 2903N * 0.0235m
τ = 68.2205 N.m

Next, we want to find the moment of inertia of the boxer's forearm by calculating the relation between torque and moment of inertia and angular acceleration,

τ = torque = 68.2205Nm
I = moment of inertia
α = angular acceleration = 130 rad / s²

τ = Iα
68.2205 = I*130rad/s²
I = 0.525 kg.m² (rounded)

Therefore, the value of moment of inertia is 0.525kg.m²

Learn more about moment of inertia https://brainly.com/question/15585759

#SPJ4

The semi-infinite body shall be considered as a system that is bounded by one surface and that extends to infinity in other directions.

To learn more about transient heat conduction refer to:

https://brainly.com/question/20493362

#SPJ4

1.065 m / s is the average speed (in m/s) of the particle.

Circumference = 2[tex]\pi[/tex]r

238.14= 2 x 3.14159 x38 cm

238.14 x 17 rotations / 38seconds

= 106.53 cm / second

106.53 cm / 100 cm per meter

= 1.065 m / s

Average speed is the total distance travelled by an object during a certain time interval. Average speed is a scalar quantity. It is represented by size and has no direction.

The formula for average speed is found by calculating the ratio of the total distance travelled by a body to the time required to travel that distance.

The average speed equation is formulated as follows:

Total distance traveled / Total time travelled

[tex]{S_{AVG}}= \frac{D_{totale}}{T_{totale}}[/tex]

To learn more about average speed, refer;

https://brainly.com/question/9834403

#SPJ4

The new acceleration would be 5.62162m/s²

Given - acceleration a=8m/s²

As per question force = F/3.7

and mass = m/2.6

To find :- new acceleration α°

Formula: F=ma

Calculation : F/3.7= [mα°]/2.6

Divide these 2 equations

2.6= 3.7(α°/a)

α°= 2.6 x 8 / 3.7

α°=5.62162m/s²

To learn more about acceleration-

https://brainly.com/question/9194964

#SPJ1

Answer:

10 m/s

Explanation:

Kinetic energy= [tex]\frac{1}{2}[/tex]mv² where m is mass and v is velocity.

We have to make v the subject so we should rearrange the equation

K=[tex]\frac{1}{2}[/tex]mv²

v²= [tex]\frac{K}{0.5*m}[/tex] (use algebra)

v²= 7/0.5×0.140

v²=100

v=√100

v=10 m/s

We can confirm this by using the kinetic energy formula.

K=[tex]\frac{1}{2}[/tex]×0.140×10²

K= 7 J

Hence it is proved that velocity is 10 m/s

When rain is falling vertically at 8m/s then the speed of the car is calculated to be 4.618 m/s.

The velocity of the raindrops adds to the velocity of the car to produce a velocity of the rain relative to the car.

As the surface becomes rougher, friction increases and on rainy days, we are more likely to slip because water acts as a lubricant between feet and the ground. Dry friction is converted to fluid friction by rainwater.  Rain drops have a uniform type of motion

Given rain is falling vertically with 8 m/s speed

and rain drop makes an angle of  30°

As we know that, tan∅ = V (horizontal) / V (vertical)

Hence,  V (horizontal)= tan ∅ *  V (vertical)

= tan (30° ) * 8

speed of the car​ = 4.618 m/s.

To know more about motion and friction, refer

https://brainly.com/question/716216

#SPJ1