7. Which of the following is true about Earth's gravity?
A. Gravity does not act on objects that are at rest or not moving.
B. Gravity only acts on oljects that are accelerating,
C. Gravity only acts on objects that are falling down.
D. Gravity acts on all objects on Earth, whether it is at rest or moving.

Answers

Answer 1

Answer:

D

Explanation:

Gravity is always having an effect on every object on earth, whether or not its moving.

Answer 2
The answer is D because gravity is gravity whether or not the object is resting or moving

Related Questions

WILL MARK BRAINLIEST JUST PLEASE HELP

Answers

Answer:

40N in either direction is the answer

The Third choice 40n in either direction will be your answer. Hope this helped. Have a great day!

A 1430 kg car speeds up from rest
to 14.0 m/s in 7.00 s. lgnoring
friction, how much power did that
require?

Answers

Energy of the car is E = m v ^2 / 2
Power is energy over time
P = E / t
So
P = (m v ^ 2)/ 2 t
P = 20 kW

The power required by the car if a 1430 kg car speeds up from rest to 14.0 m/s in 7.00 s is 20020 Joules.

What is power?

In science and engineering, power is the rate at which work is completed or energy is delivered. It can be expressed as the product of the work completed (W) or the energy transferred (E) divided by the time interval (t), or W/t.

A high-powered motor can complete a given amount of work quickly, or a low-powered motor can accomplish it slowly. Foot-pounds per minute, joules per second (or watts), and ergs per second are examples of units of power, which measure work (or energy) per unit of time.

Given:

A 1430 kg car speeds up from rest to 14.0 m/s in 7.00 s,

Calculate the acceleration and displacement as shown below,

[tex]v = u + at[/tex]

14 =  0 + a × 7

a = 2 m/s²

[tex]s = ut + 1/2at^2[/tex]

s = 0 + 1 / 2 × 2 × 7²

s = 49 m,

Calculate the power as shown below,

Power = 1430 × 2 × 49 / 7

Power = 20020 Joules

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A disk rotates at a constant angular velocity of 30 degrees per second. Consider a point on the edge of the disk. Through how many degrees has it rotated after 3 seconds?

Answers

Answer:

The disk covers a rotation of 90º after 3 seconds.

Explanation:

Since the disk rotates at constant angular speed, we can determine the change in angular position ([tex]\Delta \theta[/tex]), measured in sexagesimal degrees, by the following kinematic formula:

[tex]\Delta \theta = \omega\cdot \Delta t[/tex] (1)

Where:

[tex]\omega[/tex] - Angular velocity, measured in sexagesimal degrees per second.

[tex]\Delta t[/tex] - Time, measured in seconds.

If we know that [tex]\omega= 30\,\frac{\circ}{s}[/tex] and [tex]\Delta t = 3\,s[/tex], then the change in angular position is:

[tex]\Delta \theta = \left(30\,\frac{\circ}{s} \right)\cdot (3\,s)[/tex]

[tex]\Delta \theta = 90^{\circ}[/tex]

The disk covers a rotation of 90º after 3 seconds.

Suppose a uniform solid sphere of mass M and radius R rolls without slipping down an inclined plane starting from rest. The linear velocity of the sphere at the bottom of the incline depends on?

Answers

Answer:

None of the mass or the radius of the sphere

Explanation:

When a uniform solid sphere of any given mass, say M and any given radius, say R, rolls without slipping downwards an inclined plane that starts from rest. The linear velocity of the sphere at about the bottom of the inclined happens not to depend on either of its mass or that of the radius of its sphere.

g You heard the sound of a distant explosion (3.50 A/10) seconds after you saw it happen. If the temperature of the air is (15.0 B) oC, how far were you from the site of the explosion

Answers

Answer:

The answer is "1557 meters".

Explanation:

speed of sound in ([tex]\frac{m}{s}[/tex]) [tex]= 331.5 + 0.60 \ T^{\circ}\ C\\\\[/tex]

[tex]\to V = 331.5 + 0.6 \times 24 = 346 \frac{m}{s}\\\\\to t = 4.5 \ seconds \\\\\to S = vt = 346 \times 4.5 = 1557 \ meters[/tex]

James is planning on registering for a course in electrical engineering which of the following sub disciplines could he opt for instrumentation engineering prosthetics plant design or signal processing

Answers

Answer:

Instrmentation engineering

Explanation:

Hope this helps!

*
If a rock falls for 3 seconds off of a bridge, how far will the rock fall?
-30 m
-45m
-60m
-75m

Answers

It will fall for about 45m

Which of the factors below is NOT critical in developing good physical fitness? *

environment
behavior
age
heredity

Answers

Answer: Age

Explanation:

Physical fitness has to do with the effective and efficient working of the body system which allows individuals to be healthy.

The factors that are critical in developing good physical fitness include the environment, the behavior of the individual and heredity. To maintain physical fitness, one should exercise, eat healthy, avoid smoking etc. Age is not a factor in physical fitness.

(35) Calculate the total charge of all the electrons in a copper plate of mass 3.0g,
atomic number z = 29 and atomic mass 63.5g/mol. (Avogadro's no.- 6.02x1023
atoms, e = 1.6x10-1°C)

Answers

Given :

A copper plate of mass 3.0g.

Atomic number, z = 29.

Atomic mass, M.M = 63.5 g/mol.

Avogadro's number, [tex]N_a = 6.02\times 10^{23}\ atoms[/tex].

Charge on electron, [tex]e = 1.6\times 10^{-19}\ C[/tex].

To Find :

The total charge of all the electrons.

Solution :

Moles of copper,

[tex]m = \dfrac{3}{63.5}\ moles\\\\m = 0.047 \ moles[/tex]

Number of atoms in 0.047 moles of copper :

[tex]n = 0.047\times 6.02\times 10^{23}\\\\n = 2.83\times 10^{22} \ atoms[/tex]

Since, there are 29 electrons on each atoms.

So, total charge is :

[tex]C = 2.83\times 10^{22}\times 29\times 1.6\times 10^{-19}\ C\\\\C = 131312\ C\\\\C = 1.31 \times 10^5\ C[/tex]

Hence, this is the required solution.

A rock is at the top of a 20 meter tall hill. The rock has a mass of 10 kg. How much potential energy does it have?

Answers

Answer:

1960 J

Explanation:

The potential energy of a body can be found by using the formula

PE = mgh

where

m is the mass

h is the height

g is the acceleration due to gravity which is 9.8 m/s²

PE = 10 × 9.8 × 20

We have the final answer as

1960 J

Hope this helps you

What is the most important factor that determines the thickness, and therefore strength, of the lithosphere?

Answers

Answer:

Internal temperature

Explanation:

The temperature of the lithosphere has been said to vary across range of temperature values. From a temperature of the crust of about zero degrees Celsius (or 32 degrees Fahrenheit) to a temperature of around 500 degrees Celsius (932 degrees Fahrenheit) for that of the upper mantle. This said temperature is the most crucial factor in determining the strength, the thickness and thereof of the lithosphere

A truck pushes a pile of dirt horizontally on a frictionless road with a net force of
20

N
20N20, start text, N, end text for
15.0

m
15.0m15, point, 0, start text, m, end text.
How much kinetic energy does the dirt gain?

Answers

Answer:

300 Joules

Explanation:

This is a common question on Khan Academy's "Calculating change in kinetic energy from a force" practice exercises. (AP Physics 1)

The simplest method to use is the following: [tex]W = F * d * cos(theta)[/tex], where W represents work (joules), F represents force (newtons), d represents distance (meters), and theta represents the angle of the force that's being applied.In this scenario, the force being applied is horizontal, so we can remove the [tex]cos(theta)[/tex] from our equation.So, our equation is now: [tex]W = F * d[/tex]. This would mean that [tex]W = 20 * 15[/tex], which is equal to [tex]300[/tex]. Our answer is 300 joules. (this value is positive and not negative because kinetic energy is being GAINED, not LOST)

Here's the real question without all the formatting:

A truck pushes a pile of dirt horizontally on a frictionless road with a net force of 20 N for 15.0 m. How much kinetic energy does the dirt gain?

A truck pushes a pile of dirt in the horizontal direction with a force of 20 N to a distance of 15 m then the kinetic energy of the dirt is 300 J.

What is work?

In physics, the term "work" refers to the measurement of energy transfer that takes place when an item is moved over a distance by an externally applied, at least a portion of which is applied inside the direction of the displacement.

The duration of the path is multiplied by the component of a force acting along the path to calculate work if the forces are constant. The work W is theoretically equivalent to the pressure f times the range d, or W = fd, to represent this idea. Work is done when a force is applied at an angle of to a displacement, or W = fd cos.

The work done, [tex]W = Force * Displacement[/tex]

W = 15× 20

W = 300 J

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A bullet fired into a fixed target loses half of its velocity after penetrating 3 cm. How much further it will penetrate before coming to rest assuming that it faces constant resistance to motion​

Answers

[tex]{\mathfrak{\underline{\purple{\:\:\: Given:-\:\:\:}}}} \\ \\[/tex]

[tex]\:\:\:\:\bullet\:\:\:\sf{First \: penetrating \: length\:(s_{1}) = 3 \: cm}[/tex]

[tex]\\[/tex]

[tex]{\mathfrak{\underline{\purple{\:\:\:To \:Find:-\:\:\:}}}} \\ \\[/tex]

[tex]\:\:\:\:\bullet\:\:\:\sf{Left \: Penetration \: length \: before \: it \: comes \: to \: rest \:( s_{2} )}[/tex]

[tex]\\[/tex]

[tex]{\mathfrak{\underline{\purple{\:\:\: Calculation:-\:\:\:}}}} \\ \\[/tex]

[tex]\:\:\:\:\bullet\:\:\:\sf{Let \: Initial \: velocity = v\:m/s} \\\\[/tex]

[tex]\:\:\:\:\bullet\:\:\:\sf{Left \: velocity \: after \: s_{1} \: penetration = \dfrac{v}{2} \:m/s} \\\\ [/tex]

[tex]\:\:\:\:\bullet\:\:\:\sf{s_{1} = \dfrac{3}{100} = 0.03 \: m}[/tex]

[tex]\\[/tex]

☯ As we know that,

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ {v}^{2} = {u}^{2} + 2as }[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ \bigg(\dfrac{v}{2} \bigg)^{2} = {v}^{2} + 2a s_{1}}[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ \dfrac{ {v}^{2} }{4} = {v}^{2} + 2 \times a \times 0.03 }[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ \dfrac{ {v}^{2} }{4} - {v}^{2} = 0.06 \times a }[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{\dfrac{ - 3{v}^{2} }{4} = 0.06 \times a }[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{a = \dfrac{ - 3 {v}^{2} }{4 \times 0.06} }[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ a = \dfrac{ - 25 {v}^{2} }{2}\:m/s^{2} ......(1) }[/tex]

[tex]\\[/tex]

[tex]\:\:\:\:\bullet\:\:\:\sf{ Initial\:velocity=v\:m/s} \\\\ [/tex]

[tex]\:\:\:\:\bullet\:\:\:\sf{ Final \: velocity = 0 \: m/s }[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ {v}^{2} = {u}^{2} + 2as}[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{{0}^{2} = {v}^{2} + 2 \times \dfrac{ - 25 {v}^{2} }{2} \times s }[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ - {v}^{2} = - 25 {v}^{2} \times s }[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ s = \dfrac{ - {v}^{2} }{ - 25 {v}^{2} }}[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ s = \dfrac{1}{25} }[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ s = 0.04 \: m }[/tex]

[tex]\\[/tex]

☯ For left penetration (s₂)

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{s = s_{1} + s_{2} }[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ 0.04 = 0.03 + s_{2}}[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{ s_{2} = 0.04 - 0.03 }[/tex]

[tex]\\[/tex]

[tex]\dashrightarrow\:\: \sf{s_{2} = 0.01 \: m = {\boxed{\sf{\purple{1 \: cm }}} }}[/tex]

[tex]\\[/tex]

[tex]\star\:\sf{Left \: penetration \: before \: it \: come \: to \: rest \: is \:{\bf{ 1 \: cm}}} \\ [/tex]

Please help!!
A person is driving in a circle at 20m/s. Are they accelerating?

Answers

(C) there changing direction

Circus a path along which electric current flows how would changing the battery in a circuit from 9 V to 1.5 V most likely affect the circuit

Answers

when we reduce the voltage in circuit from 9 volts from 1.5 volts the flow of the current will also get reduced in a circuit.
yeah what he said


















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electric

what is the difference between biomass and fossil fuels main points?

Answers

Answer:

Fossil fuels release carbon dioxide into the atmosphere. Natural gas is the best fossil fuel in terms of energy output per unit of carbon dioxide emitted. Biomass is renewable because a new crop can be grown after each harvest, and biomass is a low carbon fuel. Biomass has the approximate chemical formula CHO.

Explanation:

A force of 64 N gives an object an acceleration of 23.53 m/s^2. What is the mass of the object?
A-2.00 kg
B-1505 kg
C-2.72 kg
D-736 kg

Answers

D is the right answer for this I think

air is a gas and the particles can be pushed closer toegether which is called

Answers

Gases are easily compressed, the particles have large spaces between them, so it is easy to push them closer together. Gases have very low densities, there are huge amounts of space between particles. Due to the large spaces between particles in a gas you can force the particles closer together using a plunger.

Bonnie and Clyde are trying to steal the world's largest diamond from a 10 story
building. Bonnie needs to make a landing spot for when Clyde jumps with the
diamond. She knows they will be jumping from 58 feet. Neglecting air resistance,
what is the speed Clyde will be falling at right before hitting the ground?

Answers

Answer:

The speed Clyde will be falling at is 33.72.

During a hockey game, a puck is given an initial speed of 10 m/s. It slides 50 m on the horizontal ice before it stops due to friction. What is the coefficient of kinetic friction between the pick and the ice.A) 0.12B) 0.10C) 0.11D) 0.090

Answers

Answer:

The value is  [tex]\mu_k = 0.102[/tex]

Explanation:

From the question we are told that

   The initial speed of the pluck is  [tex]u = 10 \ m/s[/tex]

    The  distance it slides on the horizontal ice is  [tex]s = 50 \ m[/tex]

Generally from kinematic equation we have that

       [tex]v^2 = u^2 + 2as[/tex]      

Here v is  is the final velocity and the value is 0 m/s given that the pluck came to rest, so

      [tex]0^2 = 10 ^2 + 2* a * 50[/tex]      

=>   [tex]a = - 1 \ m/s^2[/tex]

Here the negative sign show that the pluck is decelerating  

 Generally the force applied on the pluck is  equal to the frictional force experienced by the pluck

      So  

                [tex]F = F_f[/tex]

=>            [tex]m * a = m* g * \mu_k[/tex]

=>             [tex]1 = 9.8 * \mu_k[/tex]

=>              [tex]\mu_k = 0.102[/tex]

 

Bio-mimetic gel was used in the study of genetics and ultimately banded by the Federation. A Ferengi transport ship is carrying a 5-centimeter [cm] radius cylindrical tank of bio-mimetic gel to sell on the black market. A hydrostatic pressure probe located at the bottom of the tank reads 60 millimeters of mercury [mm Hg]. If the specific gravity of the gel is 8.9, what is the mass of gel contained in the tank in units of kilograms [kg]

Answers

Answer:

m = 6.4 kg

Explanation:

Now, we use the following equation to find the mass of the gel:

[tex]P = \rho gh[/tex]

where,

P = (60 mm of Hg)(133.3 Pa/1 mm of Hg) = 7999.2 Pa = 7.99 KPa

ρ = density of gel = [tex]\frac{m}{V} = \frac{m}{\pi r^2 h}[/tex]

m = mass of gel = ?

r = radius of cylindrical tank = 5 cm = 0.05 m

h = height of tank

Therefore,

[tex]7999.2 Pa = (\frac{m}{\pi(0.05\ m)^2\ h})(9.81\ m/s^2)h\\\\\frac{(7999.2\ Pa)(\pi)(0.05\ m)^2}{9.81\ m/s^2} = m\\[/tex]

m = 6.4 kg

I
2800000 kg
Fig. 2.1
The total mass of the rocket and its full load of fuel is 2.8 106 kg. The constant force provided by
the rocket's motors is 3.2 x 107N.
32000000 N.
(a) Calculate
(i) the total weight of the rocket and the fuel.
weight =

Answers

Answer:

W = 27468000 [N] or 27.47 [kN]

Explanation:

The weight of a body is defined as the product of mass by gravitational acceleration.

[tex]W = m*g[/tex]

where:

W = weight of the rocket with fuel [kg]

m = mass = 2800000 [kg]

g = gravity acceleration = 9.81 [m/s²]

Now we can solve:

[tex]W = 2800000*9.81\\W = 27468000 [N][/tex]

A motorcycle skids for a distance of 2.0 m with the icy road pushing on its tires with force of 120 N as its
brakes are applied
What is the change in kinetic energy for the motorcycle?
Round the answer to two significant digits.​

Answers

Answer:

-240

Explanation:

A motorcycle skids for a distance of 2.0 m on an icy road, then the change in kinetic energy for the motorcycle will be equal to -240 J.

What is kinetic energy?

The force which a moving object has is referred to as kinetic energy in physics. It is defined as the number of effort required to propel a person of a specific mass from still to a specific velocity.

Aside from slight fluctuations in speed, your body holds onto the kinetic energy it obtains during acceleration.

When the body slows down from its present level to a condition of rest, the same quantity of energy is used.

Formally, kinetic energy is any quantity that has a gradient concerning time in the Lagrangian of a system.

As per the given information in the question,

Distance, d = 2.0 m

Friction, f = 120 N

The angle between displacement and friction force, θ = 180°

Now, the change in kinetic energy for the motorcycle = Work done by the friction.

K.E = f × d(cos θ)

= 120 (2.0 m)(cos 180°)

Δ K.E = -240 J

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2 kg ball of clay moving at 40 m/s collides with a 5 kg ball of clay moving at 10 m/s directly toward the first ball. What is the final velocity if both balls stick together after the collision?

Answers

Answer:

vf = 4.3 m/s

Explanation:

Assuming no external forces acting during the collision, total momentum must be conserved:

        [tex]p_{o} = p_{f} (1)[/tex]

        where p₀ = initial momentum, and pf = final momentum.

The initial momentum is just the sum (vector sum) of the initial momenta of both balls, as follows:

       [tex]p_{o} = m_{1} * v_{1o} + m_{2} * v_{2o} = 2 kg* 40 m/s - 5kg* 10m/s = 30 kg*m/s (2)[/tex]

The final momentum, assuming both balls stick together after the collision, can be expressed as follows:

       [tex]p_{f} = (m_{1} + m_{2} ) * v_{f} = 7 kg * v_{f} (3)[/tex]

From (2) and (3), solving for vf, we get:

        [tex]v_{f} =\frac{30 kg*m/s}{7 kg} = 4.3 m/s (4)[/tex]

explain an experiment of the phenomenon of rainfall​

Answers

Unclear/incomplete question. However, I inferred you need an explanation of the phenomenon of rainfall​.

Explanation:

Basically, the phenomenon of rainfall​ follows a natural cycle called the water cycle. What we call 'rainfall' occurs when water condensed (in liquid form) in the atmosphere is made to fall down on the ground as tiny droplets as a result of the forces of gravity.

The water cycle makes rainfall possible:

First, water on the earth's surface is evaporated (or is absorbed into) the atmosphere.Next, it then condensed into liquid form; which later falls to the surface to the ground again. And the process continues.

What are conducting patterns?

Answers

Answer:

A conducting pattern is a pattern in which your dominant hand follows in order to establish beats and tempo to the choir. Conductors that are directing large orchestras and choirs will often times use a baton so that the entire group can clearly see the motions.

Explanation:

Need ASAP!! An object lies motionless on a rough inclined surface .

Answers

Answer:

yes

Explanation:

yes

Answer:

that's true

Explanation:

if the rough inclined plane was rough enough than it would be true

A major league pitcher can throw a baseball an excess of

Answers

A lions speed. You’re welcome

Can I get help on this question please

Answers

it would be the 3rd one. so C

It would be the 3rd one

20 pts.





Which of the following statements is true?
O Electromagnets use electrlcity and magnets.
O Magnetic fields are strongest around the poles of a magnet.
O The south pole of a magnet will repel the south pole of another magnet.
O all of the above

Answers

Answer:

all are true so d is right

Explanation:

Electromagnets use electrlcity and magnets is true.

Magnetic fields are strongest around the poles of a magnet is true.

The south pole of a magnet will repel the south pole of another magnet is true

and since all of them is true the answer is d all of the above

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