Objects in free fall are weightless.


Please select the best answer from the choices provided

T
F

i think correct answer is b

Answer:

Explanation:

Answer:

the upward force is equal to the passenger weight

The answer that is the truth about the force that the seat exerts on the passenger is the upward force is equal in magnitude to the passenger's weight.

The acting forces on the body has been said to be vertical. This implies that the upward force and the downward force of gravity are the same.

Using the second law of Isaac Newton, the downward direction of the forces would be ascertained.

Read more on force and magnitude here:

https://brainly.com/question/19802988

Answer:

Refractive index of the plastic = 1.46

Explanation:

By Snell's law,

[tex]\frac{\text{sin}\theta _{2} }{\text{sin}\theta _{1}}=\frac{n_1}{n_2}[/tex]

Here, [tex]\theta _1[/tex] = Angle of incidence in medium 1 (Plastic)

[tex]\theta_2[/tex] = Angle of refraction in medium 2 (Water)

[tex]n_1[/tex] = Refractive index of medium 1 (Plastic)

[tex]n_2[/tex] = Refractive index of medium 2 (Water)

By substituting values in the formula,

[tex]\frac{\text{sin}(48.7)}{\text{sin}(55.5)}=\frac{1.33}{n_2}[/tex]

[tex]n_2=\frac{1.33\times \text{sin}(55.5)}{\text{sin}(48.7)}[/tex]

    = 1.46

Therefore, refractive index of the plastic = 1.46

Answer:

v0 = 24.42 m/s (Approx)

Explanation:

Given:

Increase in frequency = 7.1% =

Computation:

Assume n = 100%

n1 = [(v+v0)/(v+v1)]n

[100 + 7.1] =  [(344+v0)/(344+0)]100

107.1 =   [(344+v0)/(344)]100

v0 = 24.42 m/s (Approx)

Answer:

The cantaloupe has a speed of 117.6 m/s

Explanation:

Free Fall Motion

It occurs when an object falls under the sole influence of gravity. Any object that is being acted upon solely by the force of gravity is said to be in a state of free fall. Free-falling objects do not face air resistance.

If an object is dropped from rest in a free-falling motion, it falls with a constant acceleration called the acceleration of gravity, which value is [tex]g = 9.8 m/s^2[/tex].

The final velocity of a free-falling object after a time t is given by:

vf=g.t

The cantaloupe has been dropped from rest. We are required to find the speed after t=12 seconds.

Calculate the final speed:

vf=9.8 * 12 = 117.6 m/s

The cantaloupe has a speed of 117.6 m/s

[tex]\huge\boxed{OptionA}[/tex]

mass = 4 kg

velocity = 5 m/s^2

Mass= 2kg

Velocity = 7m/s^2

mass = 6 kg

velocity = 4m/s^2

Mass = 8 kg

Velocity = 3 m/s^2

By the equation of kinetic energy,

                                         K.E = [tex]\frac{1}{2} mv^2[/tex]

Where,

            K.E is kinetic energy

            m is mass

            v is velocity

Directly substitute the variables in the equation,

                                       K.E = [tex]\frac{1}{2}x4x5^2[/tex]

Simplify the equation,

                                       K.E = 50 J

 Directly substitude the variable in the equation,

                                        K.E = [tex]\frac{1}{2}x6x4^2[/tex]

Simplify the equation,

                                        K.E = 48J

Substitute the variables in the equation,

                                         K.E = [tex]\frac{1}{2}x8x3^2[/tex]

Simplify the Equation,

                                         K.E = 36J

Substitute the variable,

                                        K.E = [tex]\frac{1}{2}x 2x7^2[/tex]

Simplify the equation,

                                        K.E = 49J

As you can see that the highest value of kinetic energy is of Blue SUV thus it will be out answer.

Answer:

4417

i think because

mv^2/r is centripetal force

Answer:

The minimum coefficient of static friction required, µ = 0.10

Note. The question is incomplete. The complete question is given below:

While hauling a log in the back of a flatbed truck, a driver is pulled over by the state police. Although the log cannot roll sideways, the police claim that the log could have slid out the back of the truck when accelerating from rest. The driver claims that the truck could not possibly accelerate at the level needed to achieve such an effect. Regardless, the police write a ticket anyway and now the driver court date is approaching.

The log has a mass of m = 929 kg; the truck has a mass of M = 8850 kg. According to the truck manufacturer, the truck can accelerate from 0 to 55 mph in 23.0 seconds, but this does not account for the additional mass of the log. Calculate the minimum coefficient of static friction μs needed to keep the log in the back of the truck.

Explanation:

First, velocity in mph is converted to m/s

1 mph = 0.447 m/s

55 mph ≈ 24.6 m/s

The acceleration of the empty truck is a = v/t = 24.6 / 23 = 1.07 m/s²

Force that can be generated by the truck, F = ma

F = 8850kg * 1.07 m/s² = 9469.5 N

However, with the added mass of the log on it, the acceleration of the truck will become;

a = F / m = 9469.5 N / (8550+929)kg = 0.97 m/s²

Frictional force between the log and the truck = 0.97 m/s² * 929 kg = 901.13 N

Normal reaction on the truck due to the weight of the log, R = mg

R = 929 kg * 9.8m/s² = 9104.2 N

Coefficient of static friction, µ = F/R

µ = 901.13/9104.2

µ = 0.098 ≈ 0.10

Therefore, the minimum static friction required is µ = 0.10

Answer:

29.96m/s

Explanation:

Given parameters:

Initial speed  = 25.5m/s

Acceleration  = 1.94m/s²

Time  = 2.3s

Unknown:

Final speed of the car  = ?

Solution:

To solve this problem, we are going to apply the right motion equation:

    v = u  + at

v is the final speed

u is the initial speed

a is the acceleration

t is the time taken

 Now insert the parameters and solve;

      v  = 25.5 + (1.94 x 2.3)  = 29.96m/s

Answer:

Informal education is important because it can help individual to learn how to react and control situations.

It help individual to improve on its existing knowledge, new skills or ideas. This kind of education can happen any where and it can add values to the learner.

Explanation:

Informal education is a type of education that is learned from different life experiences, happenings outside a structured curriculum.

Informal education is important because it can help individual to learn how to react and control situations.

It help individual to improve on its existing knowledge, new skills or ideas. This kind of education can happen any where and it can add values to the learner.

Answer:

7,539 m/s

Explanation:

Let's use this equation to find the gravitational acceleration of this space shuttle:

We know that G is the gravitational constant: 6.67 * 10^(-11) Nm²/kg².

M is the mass of the planet, which is Earth in this case: 5.972 * 10^24 kg.

r is the distance from the center of Earth to the space shuttle: radius of Earth (6.3781 * 10^6 m) + distance above the Earth (630 km → 630,000 m).

Plug these values into the equation:

Remove units to make the equation easier to read.

Multiply the numerator out.

Add the terms in the denominator.

Simplify this equation.

The acceleration due to gravity g = 8.11045189 m/s². Now we use the equation for acceleration for an object in circular motion which contains v and r.

a = g, v is the velocity that the space shuttle should be moving (what we are trying to solve for), and r is the radius we had in the previous equation when solving for g.

Plug these values into the equation and solve for v.

Remove units to make the equation easier to read.

Multiply both sides by 7,008,100.

Take the square root of both sides.

The shuttle should be moving at a velocity of about 7,539 m/s when it is released into the circular orbit above Earth.

Although the semi truck certainly has a larger mass, it is not in motion and therefore does not have any momentum. The bicycle however has both mass and velocity and therefore has the larger momentum of the pair.

Answer:

d) the second law of thermodynamics

Explanation:

Here we take an example

The entropy represents a measurement of the energy dispersal in the system. Also, the campfire would an entropy example. The burning of the solid wood and then it became the ash, smoke and gases this all would be spread the energy to the outward as compared to the solid fuel

Therefore as per the given statement, the correct option is d.

Answer:

66.475kJ

Explanation:

Work done is the product of the force and perpendicular distance in direction of the force.

Work done = Force × distance

Given

Weight = 700lb

Distance = 70ft

1lb force = 4.448N

700lb force = 700(4.448) = 3113.6N

Distance = 70(0.305) = 21.35m

Work done = 3113.6×21.35

Work done ≈ 66,475Joules

Work done = 66.475kJ

Answer:

 N= 3

Explanation:

For this exercise we must use Faraday's law

          E = - dФ / dt

         Ф = B . A = B Acos θ

tje bold indicate vectors. As it indicates that the variation of the field is linear, we can approximate the derivatives

         E = - A cos θ (B - B₀) / t

The angle enters the magnetic field and the normal to the area is zero

         cos 0 = 1

         A = π r²

In the length of the wire there are N turns each with a length L₀ = 2π r

          L = N (2π r)

          r = L / 2π N

    we substitute

          A = L² / (4π N²)

The magnetic field produced by a solenoid is

           B = μ₀ N/L   I

for which

            B₀ = μ₀  N/L   I

The final field is zero, because the current is zero

            B = 0

We substitute

           E = - (L² / 4π N²)  (0 - μ₀ N/L I) / t

           E = μ₀ L I / (4π N t)

           N = μ₀ L I / (4π t E)

The electromotive force is E = 0.80 mV = 0.8 10⁻³ V

let's calculate

           N = 4π 10⁻⁷ 200 1.60 / (4π 0.120 0.8 10⁻³)]

           N  = 320 10⁻⁷ / 9.6 10⁻⁶

           N = 33.3 10⁻¹

          N= 3

Answer:

6.77m/s

Explanation:

Using the law of conservation of momentum

m1u1 + m2u2 = (m1+m2)v

m1 and m2 are the masses of the object

u1 and u2 are the velocities before collision

v is the final collision

Given

m1 = 300g  = 0.3kg

u1 = 6.0m/s

m2 = 10g = 0.01kg

u2 = 30m/s

Required

The bird's speed immediately after swallowing v

Substitute the given values into the formula

m1u1 + m2u2 = (m1+m2)v

0.3(6) + 0.01(30) = (0.3+0.01)v

1.8+0.3 = 0.31v

2.1 = 0.31v

v = 2.1/0.31

v = 6.77m/s

Hence the bird's speed immediately after swallowing is 6.77m/s

Answer:

here u go

Explanation:

Earth's rotation is the rotation of planet Earth around its own axis. Earth rotates eastward, in prograde motion. As viewed from the north pole star Polaris, Earth turns counterclockwise.

Answer:the answer is “A book sitting on a high shelf” :)

Explanation:

Explanation:

Given that,

Magnitude of vector A, |A| = 15

Magnitude of vector B, |B| = 25

We need to find the magnitude of this sum.

The maximum sum of the resultant vector,

[tex]R_{max}=|A_1|+|A_2|\\\\=15+25\\\\=45[/tex]

The minimum sum of the resultant vector,

[tex]R_{min}=|A_1|-|A_2|\\\\=15-25\\\\=-10[/tex]

So, the magnitude of this sum either 45 or -10.

Answer:

a

[tex]L = 5.25*10^{7} \ m[/tex]

b

[tex]m = 1 \ kg[/tex]

c

[tex]t = 1.46112000000 *10^{11} \ s[/tex]

Explanation:

From the question we are told that

     Length  is   L  = 52500000 m

      Mass  is    

     Time  is   2435200000    minutes

Generally the proper SI for length is  meters ,

Now converting the given length to proper SI form using the appropriate prefixes we have that

             [tex]L = 5.25*10^{7} \ m[/tex]

Generally the proper SI for mass is  kilograms

converting  grams to kilograms , we have

           [tex]m =\frac{1000}{1000 }[/tex]

=>       [tex]m = 1 \ kg[/tex]

Generally the proper SI for time  is  seconds

converting  minutes  to seconds , we have

        [tex]t = 24352000000* 60[/tex]

=>      [tex]t = 146112000000 \ s[/tex]

Now converting to the  proper SI form using the appropriate prefixes

        [tex]t = 1.46112000000 *10^{11} \ s[/tex]

Answer: Kinetic Energy to Electrical.

Explanation: The magnet is rotated as a result of the spinning wheels, and this results in a powerful stream of electrons, therefore converting kinetic to electrical.

Answer:

clockwise

Explanation:

According to the law given by Lenz, known as the Lenz law, it is said that a current induced in the circuit which is due to the change in the magnetic field and is so directed so as to oppose the change in the flux and to apply a force in the opposite direction if the force.

Here, as the magnetic field is directed out of the screen, the current flows in the direction which is clockwise in the loop and it opposes the increasing magnetic field.

The clockwise induced current will produce magnetic field in to the screen.

Answer:

nearly 2 days or less hes fast but not that fast

Explanation:

but maybe he can run it in five minutes

"Radiocarbon dating is a method for determining the age of an object containing organic material by using the properties of radiocarbon."

Answer:

well for me I think

Explanation:

The use of carbon 12 to tell the age of substances

Explanation:

m means mass and v means velocity.

now, you can calculate

The change in potential energy in moving a 10kg box from the floor to a table 1 m high is 98 Joules.

To find the potential energy, the given values are,

Mass of the box = 10Kg

Height h = 1 m

The potential energy can be defined as the energy that is stored and that can be determined through various parts in a particular system.

Also, the energy will gets stored when the object is not moving.

For example: Spring. Even when the spring is not stretched or contracted it stores energy.

The formula for Potential energy PE= mgh joules.

m is the Mass,

g is the acceleration due to gravity = 9.8 m/s²,

h is the height.

Substituting all the given values,

Potential Energy= 10 (9.8)(1)

PE= 98 J

Thus the potential energy of the box= 98 J.

To learn more about the potential energy,

https://brainly.com/question/13548111

#SPJ2