A 20kg boy on a 5 kg skateboard coasts to a rest from a speed of 4.5m/s while traveling a distance of 20m on the sidewalk. Draw a free body diagram for this situation and calculate the acceleration of the skateboard, the force of friction on the skate board and the coefficient of friction between the skateboard and the sidewalk.

Answer:

 Time taken to travel remaining 228 miles = 2.4 hours.

Explanation:

Total distance = 876 miles.

Distance traveled after speed reduction = 228 miles

So, distance traveled before = 876 - 228 =648 miles.

Time taken for this = 6 hours.

Speed before speed reduction = 648/6 = 108 mph.

Speed after speed reduction = 108 - 13 = 95 mph

Time taken to travel remaining 228 miles = 228/95 = 2.4 hours.

Answer:

2.4

Explanation:

I just had this question

Formula

d = r * t

Givens

Solution

i did this in class a while ago so you multiply 20 * 3. And you answer is 60.

if you need any more help feel free to message me :)

Answer:

[tex]\frac{kg}{s^2}[/tex] or [tex]\frac{N}{m}[/tex]

Explanation:

The force in a spring is described as (F) = (k) x (d) with (d) being the displacement, measured in meters. (F) is to come out in Newtons. So (k) is assigned the appropriate unit for that to happen. The two possibilities listed above achieve that.

Answer:

The units for the spring constant k is [tex]\frac{kg}{s^2}\ \text{or}\ \frac{N}{m}[/tex].

Explanation:

According to hooks law:

[tex]F=-kx[/tex]

Where F is a force, k is spring constant and x is distance.

Here, the negative sign of the force of the spring, which implies the force of the spring, is opposed to the displacement of the spring.

Now in order to find the units for spring constant k, ignore the negative sign as we are looking only at the magnitude.

[tex]F=kx[/tex]

[tex]\frac{F}{x}=k[/tex]

Therefore,

[tex]\frac{kg}{s^2}\ \text{or}\ \frac{N}{m}[/tex]

Hence, the units for the spring constant k is [tex]\frac{kg}{s^2}\ \text{or}\ \frac{N}{m}[/tex].

Given data

Force (F) = 8480 N,

acceleration (a) = -32 m/s² ,

mass of the car (m) = ?

We know that, from Newtons II law,

                                   F = m.a

                                    => m = F ÷ a ,

                                              = 8480 ÷ (-32)

                                              = 265 Kg (Neglect negetive sign)

Mass of the car is 265 Kg

Answer ;

Note : Satellite completes  one orbit in the same time the earth rotates one about its axis

circumference of the orbit = 2 ×π × 4.23×10⁷  (similar to the earth orbital speed

The time of earth/orbit traveled  = 23.93 hrs ,

Speed of the orbit = (distance) ÷ (time)

                              = circumference ÷ time

                              = (2 ×π × 4.23×10⁷) ÷ 23.93   (1 hr = 3600 sec.)

                              = 3085.14 m/s

The orbital velocity is 3085.14 m/s

I believe the answer is transmission

When light passes straight through an object, it's called transmission. This occurs within the field of geometric optics, where light paths are modeled as straight lines or rays. These rays can change direction, or refract, when they interact with different materials.

When light passes straight through an object, it is called transmission. This is a part of the field known as geometric optics, which describes the path of light using geometry and simple trigonometry. In this field, light is modelled as straight lines, also known as rays, which may change direction when they interact with objects or transition between different media, a phenomenon known as refraction.

The laws that govern these changes in direction are the law of reflection, where light bounces off an object, and the law of refraction, where light passes through an object.

Transmission, the process in which light travels without being absorbed or reflected, is fundamental in optics. You might visualize the path of light as observable in laser beams, which is especially clear in a straight, unobstructed path.

https://brainly.com/question/3080788

#SPJ3

From my calculations The answer is B

Given Data:

Displacement of objects (s) = 4.5m,

Force applied (F) = 12 N,

Work done (W)=?

Work is defined as an effort done in order to achieve the result. In this case an effort done to move the object to certain distance.

Mathematically,  From Joules law, W =  Force  × displacement

                                                         W = 12×4.5

                                                             = 54 J

A concave mirror is used in the design of solar furnaces because they converge the parallel sunrays at a point. This helps to increase the temperature of the furnace.

Answer:

Because "a concave mirror converge the parallel sun rays at a point, so high temperature is achieved"

Example:

           It is used in the design of solar furnaces, because they converge the parallel sun rays at a point. This helps to increase the temperature of the furnace.

Answer: This is wrong The correct answer is 42.4 N

Explanation: I took the USA TESTPREP

OPTION D. The weight of the frame is determined by the upward force the two cables exert to keep it in equilibrium. Each cable exerts a vertical force of 21.2 N, totaling to 42.4 N. Thereby, the weight of the frame is 42.4 N.

This problem can be solved using the principle of forces in equilibrium. If the frame is at rest and not falling, the resultant force is zero, meaning the upward forces equal the downward forces. The tension force in the cable has components parallel and perpendicular to the direction of gravity. We only need to consider the vertical component as that is the direction of the weight of the frame.

The vertical component of the tension in one cable is given by Tsinθ = 30N * sin(45°) = 21.2 N. Since there are two cables, the total upward force is 2 * 21.2 N = 42.4 N. This equals the downward force, i.e. the weight of the frame, which is therefore 42.4 N. So, the correct answer is D).

https://brainly.com/question/30916838

#SPJ3

Given that:

mas (m) = 0.14 Kg ,

height (h) = 16 m,

     Determine gravitational potential energy ?

      Gravitational potential energy = m × g × h

                                                         = 0.14 × 9.81 × 16

                                                         = 21.97 Joules

Answer:

A.   19.3 joules

Explanation:

The collisions is perfectly elastic: this means that both total momentum and total kinetic energy are conserved after the collision.

Therefore, we can just calculate the total initial kinetic energy before the collision, and then say that it is equal to the total kinetic energy after the collision.

The kinetic energy of object A is:

[tex]K_A = \frac{1}{2}m_A v_A^2=\frac{1}{2}(7.2 kg)(+2.0 m/s)^2=14.4 J[/tex]

The kinetic energy of object B is:

[tex]K_B = \frac{1}{2}m_B v_B^2=\frac{1}{2}(5.75 kg)(-1.3 m/s)^2=4.9 J[/tex]

So, the total kinetic energy before (and after) the collision is

[tex]K=K_A + K_B=14.4 J+4.9 J=19.3 J[/tex]

Potassium is in the most reactive group of elements, the alkali metals, but it's not the most reactive metal within the group. The alkali metals, Group 1A, are the most reactive metals because they have one valence or outer electron. They lose this electron very easily, forming ions with a charge of +1.

Potassium is known as a highly reactive alkali metal due to its small ionization energy that facilitates the loss of its valence electron to form K+ ions. Its extreme reactivity is also demonstrated when it reacts with oxygen, water, and halogens, often requiring it to be stored under oil to prevent accidental reactions with air or moisture.

We know that potassium is a highly reactive alkali metal due to several characteristics. One of the key reasons for its reactivity is its small ionization energy, which makes it easier for potassium to lose its single outer-shell electron and form [tex]K^+[/tex] ions. This low ionization energy is common among alkali metals, and it allows them to form monocations easily.

Potassium's reactivity is also evident as it must be stored under oil to prevent it from reacting with air. When potassium does react with air, especially oxygen, it can cause a combination reaction that is highly exothermic. A balanced chemical equation representing this reaction with oxygen is [tex]4K + O_2 \rightarrow 2K_2O[/tex].

Furthermore, the reactivity of potassium can be seen when it is placed in water. The reaction is intense enough to produce hydrogen gas and heat, with heavier alkali metals reacting even more violently. The typical reaction with water is shown by the equation [tex]2K + 2H_2O \rightarrow 2KOH + H_2[/tex]. Finally, potassium's reactivity is demonstrated in its reactions with halogens, which are typically very exothermic and even violent.

Answer :   Equal,        Zero

If the object is moving at constant speed, it is under "equilibrium". So, forces acting on object are equal and the net force is zero.

Answer: 1687.5 N

Explanation:

From the second law of motion given by Newton, Force is the rate change of momentum.

[tex]F = \frac{dp}{dt}=\frac {m dv}{dt} = \frac{m (v_f-v_i)}{dt}[/tex]

Mass of the baseball, m = 0.15 kg

Initial velocity, [tex]v_i=-40 m/s[/tex] (negative because direction of initial velocity is opposite to the final velocity)

Final velocity, [tex]v_f=50 m/s[/tex]

The duration of collision, [tex]dt= 8.0 \times 10^{-3} s[/tex]

Force, [tex] F = \frac{0.15 kg (50-(-40) m/s)}{8.0 \times 10^{-3} s}=1687.5 N[/tex]

Hence, the value of force is 1687.5 N.

Answer:

Not sure but dont choose C .

1.3×10^3 Newtons

Explanation:

I cant find the answer anywhere but its not C so at least that gets rid of one of the options <3 (its probably not A either bc i feel like thats the closest to the other guys answer and it was rated poorly but choose at ur own risk)

Answer: positive velocity, zero acceleration

Explanation: took that on the test

Answer: option B. a car driving on a straight freeway at 60 miles.

Explanation:

A balance forces are said to act on an object when net force on an object is zero and the object is either at rest or moves with constant speed without changing direction.

In option A, C, and D the objects are changing direction during their motion. In option B, a car moves on a straight freeway in a single direction at constant speed of 60 miles per hour. Hence, the correct demonstration of balanced forces is by option B.

the answer is the car on the highway of your doing study island

Noetic science is an interdisciplinary field that aims to understand consciousness and the human mind. It stems from the Greek word 'noesis' which means inner wisdom, direct knowing, or subjective understanding. It shares some principles with physics, particularly quantum physics, but also extends beyond traditional physics to explore consciousness and subjective experiences.

Noetic science, which also aligns with concepts in cognitive science, is an interdisciplinary field that seeks to understand the nature of consciousness and the human mind. It looks into the capabilities of the mind beyond the physical realm and tries to understand phenomena like cognition and intuition.

The terms noetic science comes from the Greek word "noesis" which means inner wisdom, direct knowing, or subjective understanding. In essence, it is about investigating the nature of consciousness, going a step beyond the traditional physical sciences.

It explores the idea that consciousness isn't solely a product of the brain and attempts to bridge the gap between the objective sciences and the inner subjective experience. This would indeed fall under the wider umbrella of physics as it deals with aspects of energy and matter.

It shares some principles with physics, specifically quantum physics, in the sense that it investigates the fundamental nature of the universe and the interactions of energy and matter. However, it extends these investigations to encompass consciousness and subjective experiences which are more difficult to quantify and measure.

https://brainly.com/question/33451118

#SPJ12

Answer:

412.1 N

Explanation:

First of all let's calculate the total speed of the ball as it is released, which is equal to the speed of the ball + the speed of the bowler:

[tex]v=80.8 mph +10.0 mph=90.8 mph[/tex]

Now let's convert it into m/s. We know that

[tex]1 mph = 0.447 m/s[/tex]

So

[tex]1 mph:0.447 m/s = 90.8 mph:v\\v=\frac{(0.447 m/s)(90.8 mph)}{1 mph}=40.6 m/s[/tex]

And now we can calculate the centripetal force, which is given by:

[tex]F=m\frac{v^2}{r}[/tex]

where

m = 0.16 kg is the mass of the ball

v = 40.6 m/s is the speed of the ball

r = 0.64 m is the radius of the circular path (equal to the length of the bowler's arm)

Substituting:

[tex]F=(0.16 kg)\frac{(40.6 m/s)^2}{0.64 m}=412.1 N[/tex]

the answer is a unbalanced force is acting on the brick

Answer:

B). An unbalanced force is acting on the brick.

Explanation:

Here as we can see the given figure there are two forces acting on the block

1. [tex]F_1 = 7,205 N[/tex] Upwards

2. [tex]F_2 = 7,210 N[/tex] Downwards

so here as we can see that force downwards is more in magnitude while upward force is less.

So here since downward force is more so the box will accelerate downwards and net force is given as

[tex]F_{net} = F_2 - F_1[/tex]

[tex]F_{net} = 7210 - 7205 = 5 N[/tex]

so here net force on this box is 5 N downwards and since there is unbalanced force on the box so box can not remains at rest.

Can you provide the answers please :)

Answer:

The mass of the object on the Moon (and anywhere else) is about 30.61kg. Please see more detail below.

Explanation:

Weight is the gravitational force exerted on the object and is a function of mass and gravitational acceleration:

(weight) = (mass) x (gravitational acceleration)

We are to find the mass, knowing the weight on Earth to be 300N:

(mass) = (weight on Earth) / (gravitational acceleration on Earth) = 300N / 9.8 m/s^2 = 30.61 kg

The mass of the object is 30.61kg.

The mass of the object is independent of gravity. Therefore the answer to the question "What is its mass on the Moon" is 30.61kg.

If the question were what is its weight on the Moon, the answer would be

(weight on Moon) = (mass) x (grav.accel. on Moon) = 30.61kg x 1.62 m/s^2 = 49.59N

which is about 1/6 of the object's weight on the Earth.

Answer:

Pluto was not considered a planet because of how small it was, therefore Pluto was removed from the solar system.

False.

This is the principle of Archimedes: A body introduced into a liquid is pushed from the bottom up with a force equal to the weight of the liquid displaced by the body.

the correct answer is false

Answer:

2.35 killometers

Explanation:

As we know that mechanical advantage is defined as

[tex]MA = \frac{F_o}{F_{in}}[/tex]

now here we have

[tex]MA = 15[/tex]

also we have

[tex]F_O = 3000 N[/tex]

now we will have

[tex]15 = \frac{3000}{F_{in}}[/tex]

now we will have

[tex]F_{in} = \frac{3000}{15}[/tex]

[tex]F_{in} = 200 N[/tex]

so our applied force will be 200 N

Kinetic energy = 1/2 (mass) (speed squared)

KE = 1/2 (70kg) (2m/s)^2

KE = (35 kg) (4 m^2/s^2)

KE = (140) kg-m^2/s^2

That's 140 Newton-meter

or

140 Joules

The kinetic energy is 140 joules

The parameters given in the question are

mass= 70 kg

velocity= 2m/s

Kinetic energy= 1/2mv²

= 1/2 × 70 × 2²

= 0.5 × 70 × 4

= 140 joules

Hence the kinetic energy is 140 joules

Please see the link below for more information

https://brainly.com/question/16156066?referrer=searchResults