What must a scientist do in order to develop a testable hypothesis?

Answer:

Explanation:

B

Answer: Three forces act significantly on a freely floating helium-

filled balloon: gravity, air resistance (or drag force), and a

buoyant force.

Explanation:

The air pressure on the bottom of the balloon is slightly higher than the air pressure on the top of the balloon (because of the altitude difference). This difference gives rise to the bouyant force. This force competes with gravity as the two main forces acting on the balloon. Every time your feet hit the ground when you are running, the ground hits your feet with an equal and opposite force. Newton’s third law explains how balloons and rocket engines work. When the neck of an inflated balloon is released, the stretched rubber material pushes against the air in the balloon. The air rushes out of the neck of the balloon.

The satellite is moved to a new circular orbit that is 2R from the center of the moon, then the gravitational field strength of the moon at this new distance would be one-fourth of the initial gravitational field.

It can be defined as the force by which a body attracts another body toward its center as the result of the gravitational pull of one body and another.

As given in the problem A satellite of mass m orbits a moon of mass M in a uniform circular motion with a constant tangential speed of v. The gravitational field strength at a distance R from the center of the moon is gR. The satellite is moved to a new circular orbit that is 2R from the center of the moon.

The gravitational field strength is inversely proportional to the square of the distance from the center of the planet.

Thus, the gravitational field strength of the moon at this new distance would be one-fourth of the initial gravitational field.

To learn more about gravity here, refer to the link given below ;

brainly.com/question/4014727

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Answer

I feel the answer is C because it could cause mental and physical trauma

Explanation:

Answer:

Polarization occurs when an electric field distorts the negative cloud of electrons around positive atomic nuclei in a direction opposite the field. Polarization P in its quantitative meaning is the amount of dipole moment p per unit volume V of a polarized material, P = p/V.

Explanation:

Answer:

Polarization occurs when an electric field distorts the negative cloud of electrons around positive atomic nuclei in a direction opposite the field. Polarization( P) in its quantitative meaning is the amount of dipole moment (p) per unit volume V of a polarized material, where P = p/V.

Answer:

option (a)

Explanation:

Maintaining distance while driving in traffic can avoid the chances of an accident.                        

When the driver is behind you is trying to pass you to avoid the collision you should maintain a distance greater than 3 sec.

Hence, option (a) is correct.

Answer:

a driver behind your vehicle is trying to pass you

Explanation:

took test and checked

Answer:

The energy used for the 30-day period is 4878000 kilojoules.

Explanation:

According to the power bill, 1355 kilowatt-hours was used over a 30-day period. A kilowatt-hour is equal to 3600 kilojoules. Then, we calculate the energy used, measured in kilojoules, is determined by simple rule of three:

[tex]E = 1355\,kWh\times \frac{3600\,kJ}{1\,kWh}[/tex]

[tex]E = 4878000\,kJ[/tex]

The energy used for the 30-day period is 4878000 kilojoules.

Answer:

4770 N

Explanation:

Momentum is the product of mass and velocity and force is the change in momentum divided by change in time.

Given from the question;

Mass of arrow= 0.53 kg

Velocity of arrow = 63 m/s

Initial velocity of arrow = 0 m/s

Change in time = 0.007 s

Finding momentum after the arrow is released as;

p=m*v

p= 0.53 * 63

p= 33.39 kg*m/s

Force is the change in momentum divided by change in time;

F= 33.39 / 0.007

F= 4770 N

Answer:

On the way to the Moon the Apollo astronauts reached a point where the. Moon's gravitational pull became stronger, than the Earth's. (a) Determine the distance of ...

Explanation:

Answer:

a) The diagrams can be seen in the picture attached

(b) By comparing the diagrams we can conclude that the resultant R₁ = R₂ = R₃

Further explanation

Vector is quantity that has magnitude and direction.

One example of a vector is acceleration.

Acceleration is rate of change of velocity.

a = acceleration ( m/s² )

v = final velocity ( m/s )

u = initial velocity ( m/s )

t = time taken ( s )

d = distance ( m )

Let us now tackle the problem !

This problem is about Vector and Vector Diagram.

Given:

Vector A = -200 j

Vector B = -250 i

Vector C = (150 sin 30.0°) i + (150 cos 30.0°) j = 75 i + 75√3 j

Unknown:

R₁ = A + B + C = ?

R₂ = B + C + A = ?

R₃ = C + B + A = ?

Solution:

R₁ = A + B + C  = (-200 j) + (-250 i) + (75 i + 75√3 j)

R₁ = -175i + (75√3 - 200)j

R₂ = B + C + A = (-250 i) + (75 i + 75√3 j) + (-200 j)

R₂ = -175i + (75√3 - 200)j

R₃ = C + B + A  = (75 i + 75√3 j) + (-250 i) + (-200 j)

R₃ = -175i + (75√3 - 200)j

From the results above, it can be concluded that the resultants above produce the same results. This can be confirmed from the diagrams in the attachment.

Explanation:

Answer:

0.47m3

Explanation:

Volume = Mass / Density

In this case:

Mass - 1280 kg

Density - 2700kg/m3

1280 / 2700 = 0.4740741m3

When this is rounded off ( 2 d.p ):

0.47 m3

HOPE THIS HELPED

Answer:

Explanation:

ACCELERATION = CHANGE IN VELOCITY

                                          TIME  TAKEN

∴ a = 25 - 0

         10.5

∴ a =   50    

           21    

by using f = ma,

we get , f =   3950 ×  50                                                                                  

                                     21

∴  A FORCE OF 9404.8 N IS NEEDED TO ACCELERATE A BUS OF 3950 KG.

Answer:

18 newtons

Explanation:

Divide weight by speed

Answer:

210 ft.

Explanation:

Since a square has 4 sides and all sides are equal, just do 210 divided by 4.

Answer:

I believe it to be option A

Explanation:

Answer:2000kg

Explanation:

Convert it

Answer:

The mass of the Planet X is 9.595 x 10²⁴ kg.

Explanation:

mass of the object, m = 0.5 kg

radius of the Planet X, r = 4 x 10⁶ m

weight of the object, W = F = 20 N

let the mass of the Planet  X = mₓ

Apply Newton's gravitational law;

[tex]F = \frac{Gmm_x}{r^2} \\\\m_x = \frac{Fr^2}{Gm} \\\\m_x = \frac{(20)(4\times 10^6)^2}{6.67 \times 10^{-11} \ \times \ 0.5} \\\\m_x = 9.595 \times 10^{24} \ kg[/tex]

Therefore, the mass of the Planet X is 9.595 x 10²⁴ kg.

Answer:

P=mv

1x450,200=m40

m= 36,255kg

Answer:

W = 41.45 Kcal

Explanation:

Given that,

The mass of a person, m = 75 kg

He climbs 248 steps to the top of the Cape Hatteras lighthouse, a total climb of 59 m.

We need to find how many calories does he or she burn.

Work done = Fd

d is displacement

⇒ W = 75 ×9.8 ×59

= 43365  J

Let the efficiency is 0.25.

[tex]W=\dfrac{43365}{0.25}\\\\=173460\ J\\\\\text{or}\\\\=41.45\ kcal[/tex]

So, 41.45 Kcal is burned by the person.

Answer:

v = 24.49[m/s]    

Explanation:

We must remember that kinetic energy can be calculated by means of a mathematical expression, which relates kinetic energy to mass and velocity

[tex]E_{kin}=\frac{1}{2}*m*v^{2} \\[/tex]

where:

Ekin = kinetic energy = 12000 [J]

m = mass = 40 [kg]

v = velocity [m/s]

[tex]12000=\frac{1}{2} *40*v^{2}\\24000=40*v^{2}\\600=v^{2}\\v=\sqrt{600}\\v=24.49[m/s][/tex]

Answer:

centripital acceleration= v^2/r

r = v^2/a

r=31.8×31.8/29

r=34.8703m

Explanation:

the maximum acceleration is obtained with minimum radius.

Answer:

11. D

12. A

13. B

Explanation:

Answer:

d = 113.6 m

Explanation:

For this exercise, the first thing we must notice is that the speed of the laser beam in the fiber is constant, so we can use the uniform motion relationships to find the necessary distance

          v = d / t

let's reduce to SI units

         t = 557 ns = 557 10⁻⁹ s

         d = v t

         d = 2.04 10⁸ 557 10⁻⁹

         d = 1.136 102 m

         d = 113.6 m

This is the distance of the fiber for the laser to arrive with the desired delay

Answer:

536.56 m/s

Explanation:

We'll begin by calculating the momentum of the Porsche. This can be obtained as follow:

Mass (m) of Porsche = 1361 kg

Velocity (v) of Porsche = 26.82 m/s

Momentum of Porsche =?

Momentum = mass × velocity

Momentum = 1361 × 26.82

Momentum of Porsche = 36502.02 Kgm/s

Finally, we shall determine the velocity you need to be running with in order to have the same momentum as the Porsche. This can be obtained as follow:

Your Mass = 68.03 kg

Your Momentum = Momentum of Porsche = 36502.02 Kgm/s

Your velocity =?

Momentum = mass × velocity

36502.02 = 68.03 × velocity

Divide both side by 68.03

Velocity = 36502.02 / 68.03

Velocity = 536.56 m/s

Thus you must be running with a speed of 536.56 m/s in order to have the same momentum as Porsche.

Answer:

a) 37.70 m/s

b)710.6 m/s²

Explanation:

Given that ;

Mass of object = 2 kg

Radius of the motion = 2m

Frequency of motion = 3 rev/s

The formula to apply is;

v= 2πrf   where v is linear speed

v = 2×π×2×3 =12π = 37.70 m/s

Centripetal acceleration is given as;

a= 4×π²×r×f²  

a= 4×π²×2×3²

a=710.6 m/s²

Answer:

motion of an object—even if the object is maintaining a constant speed—still count as acceleration

Explanation:

Answer:

Nuclear Fusion reactions power the Sun and other stars. In a fusion reaction, two light nuclei merge to form a single heavier nucleus. The process releases energy because the total mass of the resulting single nucleus is less than the mass of the two original nuclei.

Explanation:

The sun's energy comes in the form of a nuclear reaction due to the Two nuclei joining to form a larger nucleus. Thus option A is correct.

A nuclear fusion is a reaction in which 2 or more atomic nuclei combine to form one or more atomic nuclei and is manifested by the release or the absorber of energy.

This is due to the differeces in the nuclear binding energy due to the force of nuclei before and after the reaction. The process releases energy as single declines less than the mass of the original nuclei.

Find out more information about the nuclear reaction.

brainly.com/question/984564

Answer:

(Total initial linear momentum = total final linear momentum.)

Momentum = mass × velocity

180×4 + 120×0 = 180×0 + 120×V

(180 ×4)/120 = V