(i) Define free fall.
0​

Answers

Answer 1

Answer:

uh,Free fall is the motion of a body where its weight is the only force acting on an object.


Related Questions

3. With a
you can measure just about anything.

Answers

MULTIMETER combines the functions of ammeter, voltmeter and ohmmeter as a minimum.

A plane took 7 hours to travel 2020 km. For the first 4 hours,
it travelled at an average speed of 310 km/h. What was the
average speed for the remaining time of the journey?
km/h

Answers

Answer:

260

Explanation:

The average speed for the remaining time of the journey is 260 km/h.

What is average speed?

The average speed of any moving object is the ratio of the total distance covered and the total time taken to cover that distance.

Given is a plane took 7 hours to travel 2020 km. For the first 4 hours,

it travelled at an average speed of 310 km/h.

Average Speed S1= distance /time

310 km/h = d/4

d = 1240 km

The remaining distance will be

2020 - 1240 = 780 km

The remaining hours are 7 - 4 =3 h

The average speed for the remaining distance is

Avg speed S2= 780 / 3

S2 = 260 km/h

Thus, the average speed of the car for the remaining is 260 km/h.

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A train starts from rest with acceleration of 0.5ms-2 find speed in Kmh-1 when it moved through 100m. (36kmh-1)

Answers

Answer:

36km/h

Explanation:

since the acceleration of the train was 0.5m/s² i.e it is constant . since the acceleration is constant you can use one of the "SUVAT" equations to find the answer.

the equation that best fits this question is: v²=u² + 2āS.

v stands for final velocity

u stands for intial velocity

v²=u² + 2āS since the car started from rest the intial velocity is zero.

v²=u² + 2āS

v²= 0 + 2(0.5m/s²)*100m

v²= 1m/s²*100m

√v²=√100m²/s²

v=10m/s

1km/hr = 1/3.6m/s

x. = 10m/s.

use criss cross method to find the value of x

x=( 1km/hr* 10m/s)

1/3.6m/s

x= 36km/hr

in most cases, letters of reconmendation are required for addmission to?

Answers

Answer:

Get your recommenders to mention diverse achievements. ...

Help your recommenders with relevant info. ...

The letter should always include examples of things you did. ...

The letter should show how you improved over time. ...

The tone of the letter should not be too dry.

What did Greek philosophers, Isaac Newton, and others commonly use to explain
their observations?
A. journals
C. hand gestures
B. math
D. interpreters

Answers

Answer:

Hey there!

They used math to explain their observations, for example, Newton is famous for his three laws, and universal laws of gravitation.

Let me know if this helps :)

Having just enough weight to achieve all three states of buoyancy with only minor adjustments in the water is the definition of:

Answers

Answer:

Proper weighting

Explanation:

Proper weighing involves the condition of a scuba diver that is fully geared having a near empty tank and the BCD emptied with a held breadth is expected to float at eye level

The fundamental of adequate or good buoyancy of a scuba diver is to ensure proper weighting when diving, With proper weighting, there is more control for the diver when a safety stop is required. There is less need to carry excess weight that increases drag and gas consumption.  

Describe a simple pendulum and, What kind of motion does it execute?

Answers

AnswerA simple pendulum is defined as an object that has a small mass, also known as the pendulum bob, which is suspended from a wire or string of negligible mass. When displaced, a pendulum will oscillate around its equilibrium point due to momentum in balance with the restoring force of gravity.A simple pendulum is defined as an object that has a small mass, also known as the pendulum bob, which is suspended from a wire or string of negligible mass. When displaced, a pendulum will oscillate around its equilibrium point due to momentum in balance with the restoring force of gravity.The repetitive to and fro motion of a pendulum is an example of periodic motion.

Perform the calculation and report your answer using sig figs. 657.70 - 26.543

Answers

Answer:

The answer is 631.157

Explanation:

The question requested that the answer to the subtraction of 26.543 from 657.70 must be written using significant figures.

Here are a few tips about how to Identify significant figures.

1) It should be noted that the number "0" is what is usually (but not always) affected while trying to identify significant figures. Hence, all other numbers/digits are always significant. For example, 26.543 has five significant figures.

2) The zeros found between these "other numbers/digits" are also significant. For example, 2202 has four significant figures.

3) In the case of a decimal, the tailing zeros or the final zero is also significant. 657.70 and 657.07 have five significant figures.

Now, back to the question

657.70  - 26.543  = 631.157.

Our final answer does not have a zero, hence all the digits (six) are significant.

A large boulder has been perched on the side of a mountain for many years. What change would cause it to suddenly roll down the mountain?

Answers

Answer:

he weight vector approaches the point within the mass, the equilibrium becomes unstable

any change in the conditions of the environment can cause the rock to slide

Explanation:

In general, a rock in a mountain is in stable equilibrium with the help of the force of gravity that causes its weight to be within the center of mass, that is, the weight vector is first and then it is electing the center of mass.

When for some reason the weight vector approaches the point within the mass, the equilibrium becomes unstable, and any change in the conditions of the environment can cause the rock to slide, for example a rain that reduces the friction force.

It may happen that the weight vector is after the center of the hubs, in this case there is an unstable balance and the stone is held in place by the force of friction with the environment that surrounds it, if this friction decreases the rock will slide .

A cosmic-ray proton in interstellar space has an energy of 10.0 MeV and executes a circular orbit having a radius equal to that of Mercuryâs orbit around the Sun (5.80Ã10^10). What is the magnetic field in that region of space?

Answers

Answer:

= 7.88 × 10^-12 T

Explanation:

From the above question, we are told that:

Kinetic Energy of the proton is K. E = 10.0 MeV

Step 1

We convert 10.0 MeV to Joules

1 Mev = 1.602 × 10-13 Joules

10.0 MeV = 10.0 × 1.602 × 10^-13 Joules = 1.602 × 10^-12 J

Hence, the Kinectic energy of a proton = 1.602 × 10^-12 J

Step 2

Find the Speed of the Proton

The formula for Kinectic Energy =

K.E = 1/ 2 mv²

Where

m = mass of the proton

v = speed of the proton

K.E of the proton = 1.602 × 10^-12 J

Mass of the proton = 1.6726219 × 10^-27 kilograms

Speed of the proton = ?

1.602 × 10^-12J = 1/2 × 1.6726219 × 10^-27 × v²

1.602 × 10^-12J = 8.3631095 ×10^-28 × v²

v² = 1.602 × 10^-12/8.3631095 ×10^-28

v = √(1.602 × 10^-12/8.3631095 ×10^-28)

v = 43772331.227m/s

v = 4.3772331227 × 10^7m/s

Approximately = 4.4 × 10^7 m/s

Step 3

Find the Magnetic Field of that region of space

The formula for Magnetic Field =

B = m v / q r

We are told that the proton executes a circular orbit, hence,

mv = √2m(KE)

m = Mass of the proton = 1.6726219 × 10^-27 kg

K.E of the proton = 1.602 × 10^-12 J

v = speed of the proton = 4.4 × 10^7 m/s

q = Electric charge = 1.6 × 10^-19 C

r = radius of the orbit = 5.80Ã10^10 m

= 5.8 × 10^10m

Magnetic Field =

=√ (2 × 1.6726219 × 10^-27 kg × 1.602 × 10^-12 J) /( 1.6 × 10^-19 C × 5.80 × 10^10 m)

= 7.88 × 10^-12 T

The magnetic field in that region of space is approximately 7.88 × 10^-12 T

You are out on the water in foggy conditions. You hear one prolonged blast plus two short blasts every two minutes. What does this sound signal mean?

Answers

The sound signal helps to caution and let other people know the exact

position or location during sailing in limited visibility conditions.

Sailors are in which charge of controlling and movement of ships. In limited

visibility conditions such as during fogs, one prolonged blast plus two short

blasts every two minutes are done.

This helps to alert people and other sailors of their location at sea to prevent

accidents and death.

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The sound signal helps to know the exact location during sailing in foggy conditions.

Who are sailors?


Sailors are the in charge of controlling and movement of ships. In limited visibility conditions such as fogs, one prolonged blast plus two short blasts every two minutes are done.

This helps to caution people and other sailors around their location at the sea to prevent accidents and death.

Learn more about Sailors

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A bird flew 100 meters in 2 minutes. What was the birds speed ? (show all your work below)

Answers

Answer:

speed = 50 metres/minute

Explanation:

Distance traveled = 100 metres

Time taken =- 2 minutes

Speed =[tex]\frac{Distance }{Time}[/tex]

speed =[tex]\frac{100}{2}[/tex]

speed = 50 metres/minute

The speed of a bird that flies 100 meters in 2 minutes is 0.83 m/s.

The speed is a scalar magnitude defined as the quotient of the distance traveled and the time, as follows:  

[tex] s = \frac{d}{t} [/tex]

Where:

d: is the distance = 100 m

t: is the time = 2 min

Hence, the bird's speed is:

[tex] s = \frac{d}{t} = \frac{100 m}{2 min} = 50 \frac{m}{min}*\frac{1 min}{60 s} = 0.83 m/s [/tex]

Therefore, the bird's speed is 0.83 m/s.

You can see another example of speed calculation here: https://brainly.com/question/312131?referrer=searchResults

I hope it helps you!

               

The force of gravity pulls down on your school with a total force of 400,000 newtons. The force of gravity pulling down on your school would be exactly twice as much if your school:

a Had twice as much mass b Was twice as tall c Had twice as much volume d Covered twice as much area

Answers

Answer: A) Had twice as much mass

Explanation:

Given that the force of gravity pulling down on school = 400,000 N

The force of force of gravity is the product of mass of the body and the acceleration due to gravity. The acceleration due to gravity is constant on the earth surface with a constant value of 9.8m/s²

Hence,

F = mg = 800N

F = force of gravity, m = mass of body, g =! acceleration due to gravity.

since g is constant, to have 2F, then mass has to be doubled, that is 2m(2 * mass)

Which of the following is not a velocity?*
25 m/s south
100 km/s east
O 50 mph
10 ft/s up
O​

Answers

Answer:

50 mph

Explanation:

doesn’t have direction

50 mph is not a velocity bcos it doesn't have direction

A dolphin emits a sound wave that hits a target 120 m away. The wave reflects back from the target to the dolphin. If the Bulk modulus of seawater is 2.3 x 10° N/m2 and the density of seawater is 1022 kg/m3. How long does it take the sound wave for the round trip?

Answers

Answer:

The time taken for the sound wave to make the round trip is 0.16 s.

Explanation:

Given;

distance traveled by the sound wave, d = 120 m

bulk modulus of sea water, B = 2.3 x 10⁹ N/m²

density of sea water, ρ = 1022 kg

The speed of the wave is given by;

[tex]v = \sqrt{\frac{B}{\rho} } \\\\v = \sqrt{\frac{2.3*10^9}{1022} }\\\\v = 1500.16 \ m/s[/tex]

Speed is given by;

[tex]Speed = \frac{Distance}{Time}[/tex]

total distance of the round trip = 2 x 120m = 240 m

Time taken for the sound wave to make the round trip is given by;

[tex]Time = \frac{Distance}{Speed} \\\\Time = \frac{240}{1500.16} \\\\Time = 0.16 \ second[/tex]

Therefore, the time taken for the sound wave to make the round trip is 0.16 s.

A stone is thrown in a vertically
upward direction with a velocity
of 5 ms. If the acceleration of the
stone during its motion is 10 ms?
in the downward direction, what
will be the height attained by the
stone and how much time will it
take to reach there?

Answers

Answer:

1.25 m

0.5 s

Explanation:

Given:

v₀ = 5 m/s

v = 0 m/s

a = -10 m/s²

Find: Δy

v² = v₀² + 2aΔy

(0 m/s)² = (5 m/s)² + 2 (-10 m/s²) Δy

Δy = 1.25 m

Find: t

v = at + v₀

(0 m/s) = (-10 m/s²) t + (5 m/s)

t = 0.5 s

Which property of an object is the result of gravity?
A.mass
B.weight
C.volume
D.velocity
PLEASE ANSWER AS FAST AS POSSIBLE

Answers

Answer:

A. Mass

Explanation:

Answer:

Weight

Explanation:

Which equation could be rearranged to calculate the frequency of a wave?
wavelength = frequency/speed
frequency = wavelength/speed
wavelength = speed/frequency
frequency = speed x wavelength​

Answers

Answer:

wavelength = speed/frequency

Explanation:

Required

Determine which of the options can be used to calculate frequency

The relationship between wavelength, speed and frequency is as follows;

[tex]Frequency = \frac{Wave\ Speed}{Wave\ Length}[/tex] ---- Equation 1

When option (1), (2) and (4) are rearranged, they do not result in the above formula; only option (3) does

Checking option (3)

[tex]Wave\ Length = \frac{Speed}{Frequency}[/tex]

Multiply both sides by Frequency

[tex]Wave\ Length * Frequency = \frac{Speed}{Frequency} * Frequency[/tex]

[tex]Wave\ Length * Frequency = Speed[/tex]

Divide both sides by Wave Length

[tex]\frac{Wave\ Length * Frequency}{Wave\ Length} = \frac{Speed}{Wave\ Length }[/tex]

[tex]Frequency = \frac{Speed}{Wave\ Length }[/tex] --- Equation 2

Comparing equation 1 and 2; both equations are the same.

Hence, option (3) answers the question

Answer:

wavelength = speed/frequency

Explanation:

Required

Determine which of the options can be used to calculate frequency

The relationship between wavelength, speed and frequency is as follows;

---- Equation 1

When option (1), (2) and (4) are rearranged, they do not result in the above formula; only option (3) does

Checking option (3)

Multiply both sides by Frequency

Divide both sides by Wave Length

--- Equation 2

Comparing equation 1 and 2; both equations are the same.

Hence, option (3) answers the question

I WILL GIVE BRAINLIEST!! :) The value of the total current is: A. 3.5A B. 4.0 A C. 4.5A D. 5.0 A

Answers

Answer:

Option C. 4.5 A

Explanation:

We'll begin by calculating the equivalent resistance of R1 and R3. This can be obtained as follow:

R1 = 6 Ω

R3 = 3 Ω

Equivalent of R1 and R3 =?

Since R1 and R3 are in parallel connections, we shall their equivalence as follow:

Equivalent of R1 and R3 = (R1×R3) /(R1 + R3)

Equivalent of R1 and R3 = (6×3)/(6+3)

Equivalent of R1 and R3 = 18/9

Equivalent of R1 and R3 = 2 Ω

Next, we shall determine the equivalent resistance in the circuit.

This is illustrated below:

R2 = 2 Ω

Equivalent of R1 and R3 = 2 Ω

Equivalent resistance (R) in the circuit =?

Note: Equivalent of R1 and R3 is in series connection with R2.

Equivalent Resistance (R) = (Equivalent of R1 and R3) + R2

Equivalent Resistance (R) = 2 + 2

Equivalent Resistance (R) = 4 Ω

Finally, we shall determine the total current in the circuit as follow:

Potential difference (V) = 18 V

Equivalent Resistance (R) = 4 Ω

Current (I) =.?

From ohm's:

V = IR

Where V is the potential difference.

I is the current.

R is the resistance.

V = IR

18 = I × 4

Divide both side by 4

I = 18/4

I = 4.5 A

Therefore, the total current in the circuit is 4.5 A.

When a sacred item or symbol is removed from its special place or is duplicated in mass quantities, then it becomes profane as a result of ________.

Answers

Answer:

It becomes profane as a result of desacralization

Explanation:

Because desacralization means when a dedicated religious structure is no longer used for its intended purpose both rather used for another purpose other than the original purpose

El momento lineal de un coche que viaja hacia el norte a 20m/s es distinto al momento lineal del mismo auto viajando hacia el este con la misma rapidez.

Answers

Explanation:

The momentum of any object is given by the product of mass and velocity with which it is moving i.e.

p = mv

Momentum is a vector quantity. It means we can resolve it into rectangular components.

If the car is moving with a speed of 20 m/s in North direction, its momentum is given by :

[tex]p_y=20m\ \hat{j}\ kg-m/s[/tex] .....(1)

If the car is moving with a speed of 20 m/s in East direction, its momentum is given by :

[tex]p_x=20m\ \hat{x}\ kg-m/s[/tex] ....(2)

It is clear from equation (1) and (2) that the magnitude of momentum is same but the direction of momentum is different in both cases.

Two students are watching a person riding a skateboard up and down a ramp. Each student shares what they think about the energy of the skateboarder as they ride up and down the ramp.

Elisa: I think the skateboarder has the more total energy at the top bottom of the ramp than the bottom of the ramp.

Raymond: I think the skateboarder has the same total energy at all points on the ramp.

Which student do you agree with? Why?

Answers

Answer:

The correct option is;

Raymond: I think the skateboarder has the same total energy at all points on the ramp

Explanation:

The total energy, also known as the total mechanical energy, is the sum of the kinetic and potential energies of the skateboarder

Given that the potential energy is the energy gained due to elevation, the maximum potential energy is obtained at the top of the ramp, while the maximum kinetic energy, which is the energy due to motion, is at the bottom of the ramp where the skateboarder moves fastest.

However, by the energy conservation principle, the kinetic energy of he skateboarder comes from the conversion of the potential energy, such that the total energy is the same at any particular point on the ramp.

A cement block accidentally falls from rest from the ledge of a 55.9-m-high building. When the block is 11.2 m above the ground, a man, 1.70 m tall, looks up and notices that the block is directly above him. How much time, at most, does the man have to get out of the way?

Answers

Answer:

0.3 seconds approximately

Explanation:

Given that the height of the building is 55.9 m and cement block accidentally falls from rest from the edge of a 55.9-m-high building. The initial velocity of the block will be equal to zero. The final velocity will be achieved by using the formula:

V^2 = U^2 + 2gH

Where g = 9.8 m/s^2

H = 55.9m

V^2 = 0 + 2 × 9.8 × 55.9

V^2 = 1095.64

V = sqrt(1095.64)

V = 33.1 m/s

The velocity When the block is 11.2 m above the ground will be 33.1 m/s and the height h = 11.2 - 1.7 = 9.5 m

The time of escape can be calculated by using the formula;

h = Ut + 1/2gt^2

9.5 = 33.1t + 1/2 × 9.8 × t^2

9.5 = 33.1t + 4.9t^2

4.9t^2 + 33.1t - 9.5

By using quadratic formula to calculate the time, the negative value is ignored and the positive values will be the time the man has to get out of the way.

Please find the attached file for the remaining solution.

A body when dropped into a jar ,containing kerosene and glycerine ,sinks below the kerosene level to float in glycerine as infig .What can we say about the densities of kerosene ,glycerine and the body

Answers

Answer:

we can say that that in an increasing order, the body is less dense than the glycerine, and the glycerine is less dense than the kerosene.

Explanation:

If the body sinks below the kerosene level to float in glycerine, then it means that the kerosene is denser than glycerine. This is because bodies will float higher in a denser fluid that a less denser fluid. Also, since the body floats in kerosene and glycerine, then the body is less dense than the kerosene and the glycerine. Finally, we can say that that in an increasing order that the body is less dense than the glycerine, and the glycerine is less dense than the kerosene

Which statement is accurate about mass or weight?

Mass can be measured in newtons.
Weight can be measured in pounds.
A bowling ball has the same mass as a golf ball.
Objects have the same weight regardless of where they are.

Answers

Answer:

Wright can be measured in pounds

Explanation:

Mass is the quantity of matter a body contains while weight is the measure of mass of a body. Weight is the product if mass and the acceleration due to gravity of a body.

If the mass of an object is known, we can determine the equivalent weight of such object and vice versa using the relationship W = mg

m is the mass if the object (in kg)

W is the weight

g is the acceleration due to gravity

g can be measured both on metre/seconds or lb/ft². This means that the weight of an object can be measured in both kgm/s² (Newton) and lb(pounds).

Also note that different object have different masses hence it is not always true to say that a bowling ball has the same mass as a golf ball.

Based on the explanation above, it can be concluded that Weight can be measured in pounds which gives the only correct statement.

Answer:

Weight can be measure in pounds

Explanation:

lab safety test Safety goggles and an apron must be worn when handling chemicals labeled corrosive because they:________.

Answers

Answer:

The terms of biosafety in a laboratory require that the person must not have the eyes and skin exposed.

Explanation:

A corrosive substance is a substance that can damage a surface when they come into contact.

These substances represent a danger in people since they can burn the eyes, the skin, and the inside of the body since the inhalation of gases can burn the respiratory tract.

These chemical burns can be avoided by properly following the biosafety protocol that a laboratory requires the use of masks, goggles, gloves, and an apron or lab coat.

What subatomic particle identified this atom

Answers

Answer:

protons

Explanation:

the protons identifies an atoms as that of a particular element the atomic number is equal to the number of protons in the nucleus of an atom

which phrase describes what a scientist does? A.Tells People how they should behave B .Answers ethical questions C. Ask questions about the world D. Determines right from wrong

Answers

Answer:

C. Ask questions about the world

Explanation:

A scientist is a person who conducts scientific research and provide scientific proves on the area of their interest such as physica, chemistry, biology or history.

A scientist gives the answers of the question about the world based on their scietifc research such as how does plant breath? effects of global warming on earth? what if we don't drink water for a particular time period? et-cetera.

Hence, the correct option is "C. Ask questions about the world".

During first half of a journey by a body it travel with a speed of 40km/hr and in the next half it travels with a speed of 20 km/hr .Calculate the average speed of the whole journey.​

Answers

Answer:

Average speed = 26.67 km/h

Explanation:

It is given that,

The first half of the journey by a body is traveled with a speed of 40 km/h and the next half is covered with a speed of 20 km/h

We need to find the average speed of the whole journey.​ When two speeds are given, the average speed is given by :

[tex]v=\dfrac{2v_1v_2}{v_1+v_2}\\\\v=\dfrac{2\times 40\times 20}{40+20}\\\\v=26.67\ km/h[/tex]

So, the average speed of the body of the whole journey is 26.67 km/h.

(b) The table below shows the mass and volume of four objects.
object
mass (g)
volume (cm)
aluminium figure
230
85
lead weight
800
70
steel block
200
25
wood puzzle
400
500
(i) Which object is the heaviest? *
Tour answer​

Answers

Answer:

I think lead is the heaviest one

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