A car is moving at 30km/h. What is its speed in m/s? Give your answer to 2 significant figures.

Answer:

Air.

Explanation:

To know which option is correct, let us consider the relationship between velocity and the wavelength of a wave. This is illustrated below:

Velocity, wavelength and frequency are related by the following equation:

Velocity = wavelength × frequency

v = λf

From the equation above, we can see clearly that the velocity is directly proportional to the wavelength.

This means that an increase in the wavelength will lead to an increase in the velocity and also, a decrease in the wavelength will lead to a decrease in the velocity.

Now, considering the table given in the question above, we can see that the wave has a higher speed in air. This simply means that the wave will also have a higher wavelength in air.

Thus, the correct answer to the question is: air

Answer:

Etc....

Explanation:

#keep learning!!

Explanation:

POTENTIAL energy is the energy that is stored in an object due to its position relative to some zero position.

Answer: Re-Horakhty

Explanation:

He has a human body and a falcon head, he has a crown in form of a disk with a cobra on his head. Ra-Horakhty was thought of as the god of the rising sun.

Answer:

Explanation:

The formula for centripetal acceleration is

[tex]a_c=\frac{v^2}{r}[/tex] . Filling in:

[tex]2.5=\frac{v^2}{15}[/tex] and

[tex]v=\sqrt{2.5(15)}[/tex] so

v = 6.1 m/s

Answer: C- the outer core

Explanation: The outer core is a thick layer of molten rock that encircles the inner core.

Answer:

[tex]\triangle \phi=461.5rad[/tex]

Explanation:

From the question we are told that:

Silt width [tex]w=0.15=>0.1510^{-3}[/tex]

Wavelength [tex]\lambda=462nm=462*10^{-9}[/tex]

Angle [tex]\theta=26.9[/tex]

Generally the equation for Phase difference is mathematically given by

[tex]\triangle \phi=\frac{2 \pi}{\lambda}(\frac{wsin\theta }{2})[/tex]

[tex]\triangle \phi=\frac{2 \pi}{462*10^{-9}}(\frac{0.1510^{-3}*sin 26.9 }{2})[/tex]

[tex]\triangle \phi=461.5rad[/tex]

[tex]\triangle \phi=146.89\pi[/tex]

Answer:

The entire rainbow of radiation observable to the human eye only makes up a tiny portion of the electromagnetic spectrum – about 0.0035 percent. This range of wavelengths is known as visible light.

Explanation:

Please Mark me brainliest

Answer:

It is proved.

Explanation:

PV = n R T

where,  P is the pressure, V is the volume, n is the number of moles, R is the gas constant, T is  the absolute temperature.

Unit of pressure is Pascal= Newton/square meter = [tex][ML^{-1}T^{-2}][/tex]

Unit of volume is cubic meter = [tex][L^{3}][/tex]

So, the unit of P V

[tex][ML^{-1}T^{-2}] \times [L^{3}]\\\\[ML^2T^{-2}}[/tex]

[tex][ML^{2}T^{-2}][/tex]

It is same as the unit of energy.

hence proved.  

Answer:

Two equal and opposite parallel forces not acting along the same line, form a couple. A couple is always needed to produce the rotation.

For example, turning a key in a lock and turning a steering wheel.

Answer:

cemento potque es plano

Answer:

Option (D)

Explanation:

A. The nucleus of one atom and the electron cloud of the another atom will not the cause of attraction.

B. The nucleus of one atom and the other atom will not cause the attraction.

C. The electron cloud of one atom and the electron cloud of the another will not cause attraction.

D. So, this option is correct.

Answer:

I think it's D

Explanation:

because I have seen the tracks of the tires

Answer:

The action of measuring the size, length, or amount of something, as established is called measurement.

Explanation:

“Measurement” is the act of determining a target's size, length, weight, capacity, or other aspect. ... To use measurement tools as necessary. It is also appropriate to say that measurement is done by a worker using a measurement system, and instrumentation is done by a technician.

Answer:

t=1/4v1

Explanation:

Given data

Car one

Speed =v1

Time =t

Distance =1/4 mile

Given data

Car two

Speed =v1/2

Time =t

Distance =d

Speed =distance/time

v1=1/4/t

v1t=1/4

t=1/4*1/v1

t=1/4v1 seconds

Answer:

The magnetic force acting on the proton is 1.68 x 10^-18 N.

Explanation:

magnetic field, B = 5 T

speed , v = 2.1 m/s

charge q = 1.6 x 10^-19 C

Angle, A = 90 degree

The magnetic force on the charge particle is given by

[tex]F = q v B sin A\\\\F = 1.6\times 10^{-19}\times 2.1\times 5\times sin 90\\\\F = 1.68\times 10^{-18} N[/tex]

Answer:

(4) A = 3 A, A₂ = 11 A

(5) 7 A

Explanation:

(4)

From the diagram,

A = 3+6+2

A = 11 A

V = A₂R

A₂ = V/R₂............ Equation 1

Given: V = 12 V,  R₂ = 4 Ω

Substitute these values into equation 1

A₂ = 12/4

A₂ = 3 A

(5) Applying,

V = IR'

I = V/R'............ Equation 1

Where V = Voltage, I = cuurent, R' = total resistance.

But,

1/R' = (1/3)+(1/4)

1/R' = (3+4)/12

1/R' = 7/12

R' = 12/7 Ω

Given: V = 12 V

Substitute these values into equation 1

I = 12/(12/7)

I = 7 A

Therefore

A = 7 A

it will hit the ground maybe in like 1 second I guess

Answer:

1kg = 1000g

67kg therefore would be equal to

67 x 1000 = 67,000g = 6.7 x 10⁴g.

[tex] \green{\huge{\red{\boxed{\green{\mathfrak{QUESTION}}}}}} [/tex]

Define Circular motion and its types

[tex] \huge\green{\boxed{\huge\mathbb{\red A \pink{N}\purple{S} \blue{W} \orange{ER}}}}[/tex]

[tex]{ \red{ \bold {\mathbb {\textit{Circular \: motion}}}}}[/tex]

MOTION OF THE BODY CIRCULAR PATH IS CALLED CIRCULAR MOTION

[tex]{ \blue {\bold{UNIFORM \: CIRCULAR}}} \\ \green{ \bold{ MOTION}}[/tex]

[tex] { \green{ \bold{ NON UNIFORM}}} \\ {\blue{ \bold{CIRCULAR \: MOTION}}}[/tex]

Velocity is vector quantity because it has both magnitude and direction.

Explanation:

velocity is a vector quantity because the person always returns to the original position,the motion would never result in a change in a position.

Answer:

Coulomb, unit of electric charge in the metre- kilogram- second- ampere system, the basis of SI system of physics unit. The coulomb is defined as the quantity of electricity transported in one second by a current of one ampere.

Answer:

Answer:

Determine the direction that the pilot is aiming the plane.

Explanation:

Answer:

(a) i) The distance travelled by the cycle in half round is approximately 65.97 m

ii) The displacement is 42 m

(b) (i) The distance travelled in one round is approximately 131.95 m

(ii) The displacement of the cycle in one round is 0

Explanation:

The diameter of the track through which the cycle travels, D = 42 m

(a) i) Half round is the motion of half the length of the circular path

The distance travelled by the cycle in half round = The length of half the circular track = (1/2) × π × D

∴ The distance travelled by the cycle in half round = (1/2) × π × 42 m = 21·π m ≈ 65.97 m

ii) The displacement half round = The change in the location of the cycle = The difference between the start and stop locations of the cycle on a straight line after half round

The angle at the center of the circular path the cycle turns in half round  = 180°

Therefore, the path between the start and stop location of the cycle in half round = The diameter of the circular track

The displacement of the cycle in half round = The diameter of the circular track = 42 m

(b) (i) The distance travelled in one round = The perimeter of the circular track = π·D

∴ The distance travelled in one round = π × 42 m ≈ 131.95 m

(ii) The displacement of the cycle in one round = The change in the location of the cycle

The start and stop location of the cycle after moving one round is the same, therefore, there is no change in the location of the cycle.

Therefore we have;

The displacement of the cycle in one round = 0 (no change in location of the cycle)

Answer:

2.8 hours

Explanation:

98 ÷ 35 = 2.8

Answer:

The surface gravity g of the planet is 1/4 of the surface gravity on earth.

Explanation:

Surface gravity is given by the following formula:

[tex]g=G\frac{m}{r^{2}}[/tex]

So the gravity of both the earth and the planet is written in terms of their own radius, so we get:

[tex]g_{E}=G\frac{m}{r_{E}^{2}}[/tex]

[tex]g_{P}=G\frac{m}{r_{P}^{2}}[/tex]

The problem tells us the radius of the planet is twice that of the radius on earth, so:

[tex]r_{P}=2r_{E}[/tex]

If we substituted that into the gravity of the planet equation we would end up with the following formula:

[tex]g_{P}=G\frac{m}{(2r_{E})^{2}}[/tex]

Which yields:

[tex]g_{P}=G\frac{m}{4r_{E}^{2}}[/tex]

So we can now compare the two gravities:

[tex]\frac{g_{P}}{g_{E}}=\frac{G\frac{m}{4r_{E}^{2}}}{G\frac{m}{r_{E}^{2}}}[/tex]

When simplifying the ratio we end up with:

[tex]\frac{g_{P}}{g_{E}}=\frac{1}{4}[/tex]

So the gravity acceleration on the surface of the planet is 1/4 of that on the surface of Earth.

Answer:

The answer is "thumb-up".

Explanation:

The sling often called the arm sling, is a solution for preventing either shoulder or elbow motion during healing. A triangle bandage could be constructed.

A sling is a strong tissue loop that descends from the head to hold the forearm. The armrests in the sling bent also at the elbow.

The injured hand of the forearm should be positioned inside the pin position in the joint above the level of the elbow when putting the forearm sling.

Answer:

1.the friction of air, gravity2.gravity

Answer:

The softball experiences an applied force as a result of Amy’s throw. As the ball moves, it experiences drag from the air it passes through. It also experiences a downward pull because of gravity.

Explanation:

Plato

Answer:

the efficiency of the machine is 100%

Explanation:

Given;

load, L = 750 N

length of the lever, L = 2 m

effort applied, E = 250 N

Position of the load from the fulcrum,  = 50 cm

                                     50cm

     0↓--------------------------Δ-------------------------------↓---------200 cm

    750 N                                       x cm                 250 N

Apply the principle of moment;

750(50) = 250(x)

x = (750 x 50) / (250)

x = 150 cm

the distance of the effort = 150 cm = 1.5 m

the distance of the load = 50 cm = 0.5 m

The velocity ratio of the machine = 1.5/0.5

                                                        = 3

The mechanical advantage of the machine is calculated as;

M.A = Load/effort

M.A = 750 / 250

M.A = 3

The efficiency of the machine is calculated as;

E = (M.A / V.R) x 100%

E = (3/3) x 100% = 100%

Therefore, the efficiency of the machine is 100%

Answer:

[tex]a=0.33\ m/s^2[/tex]

Explanation:

For washer 2,

v₁ = 0.13 m/s

v₂ = 0.36 m/s

t₁ = 1.92

t₂ = 2.61

We need to find the acceleration of waster 2.

[tex]a=\dfrac{v_2-v_1}{t_2-t_1}\\\\a=\dfrac{0.36-0.13}{2.61-1.92}\\\\a=\dfrac{0.23}{0.69}\\\\a=0.33\ m/s^2[/tex]

So, the acceleration of washer 2 is [tex]0.33\ m/s^2[/tex].

Answer:

.33

Explanation: