why is earth a magnet?

Answer:

The required velocity of runner is 4m/s.

Answer:

A................

Explanation:

Hope this helps you

A. increase it's current and increase it's voltage

Explanation:

Answer:

280 N

Explanation:

acceleration = v2-v1 / time taken = (2-4 )/ 0.05 = -40 m/s^2  ( neg sign indicates slowing down )

force exerted = ma = 7 kg x -40 m/s^2 = - 280 N ( neg sign means opposite direction of initial velocity )

since the 7 kg ball is slowing down, the  direction of force will be opposite of the initial velocity , and it will be 280 N

Answer:

b

Explanation:

bbhbh

The genes for green color are dominant over the genes for brown color because all the beetle offspring have a green phenotype. Therefore, option (D) is correct.

In biology, a phenotype can be described as the observable characteristics of an organism which is the result of the interaction of environmental factors and genes. These traits involve physical appearances and any traits that we can observe.

The phenotype includes its physiological, biochemical, as well as behavioral properties. Genotype is inherited from the parents while the phenotype can be affected by lifestyle and environmental factors. Environmental factors such as nutrition, temperature, humidity, and mental health of the organism.

For example, flamingoes are white in color but turn pink because of the pigments they need from their diet. Therefore, flamingoes portray how they are affected by environmental factors. The phenotype of an organism changes, accordingly to environmental factors.

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Answer:

In physics and chemistry, the law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be conserved over time. ... For instance, chemical energy is converted to kinetic energy when a stick of dynamite explodes.

Answer:

12m/s2

Explanation:

:D (just a smiley, not answer d)

Answer:

It doesn't change. It stays the same.

I hopes this helped you and if it did I'm glad I helped someone!!!

Explanation:

Answer:

8000cm³/hr

Explanation:

Given parameters:

Volume of the liquid draining off per hour   = 8000cm³

Time taken to drain off  = 1hr

Unknown:

Flow rate  = ?

Solution:

Flow rate is the volume of fluid that passes per unit of time.

 Flow rate  = [tex]\frac{volume of fluid}{time taken}[/tex]  

 Flow rate  = [tex]\frac{8000cm^{3} }{1hr}[/tex]  

Flow rate  = 8000cm³/hr

Answer:

It would be cut in half.

Explanation:

If the momentum of the ball is cut into half, the velocity will also be halved.

The momentum of a body is the amount motion a body possess.

Momentum is given as;

       momentum= m x v

Given that;

 mass  = 1kg

 velocity  = 12m/s

Now find the momentum;

            momentum  = 1 x 12 = 12kgm/s

Halving the momentum = 6kgm/s

              mass = 1kg

 Momentum  = 1 x v

       6  = 1 x v

           v  = 6m/s

We see that the velocity reduces by half

Answer:

It would be doubled.

Explanation:

I'm in K12

Answer:

The answer is "[tex]5 \ \frac{m}{s} \ west[/tex]"

Explanation:

[tex]\to \vec{V_1} = (25 \frac{m}{s}) (\hat{-i})\\\\\to \vec{V_2} = (20 \frac{m}{s}) (\hat{-i})\\\\[/tex]

velocity of car | respect to car :

[tex]\to \vec{V_{12}} = \vec{V_1} - \vec{V_2}\\\\[/tex]

          [tex]=\vec{-25} \hat{i}+ \vec{20} \hat{i}\\\\= 5 \ \frac{m}{s} \ west[/tex]

Answer:

70 m/s east

Explanation:

Answer:

1.2 W

Explanation:

Let the value of resistance be R , emf of battery be E

current i = E / R

power = i² R

= E² x R / R²

= E² / R

Given

E² / R = .30

when two batteries are connected

Total emf = 2E

current = 2E / R

Power = ( 2E / R )² x R

= 4 E² / R

= 4 x .30

= 1.2 W .

Answer: B. The speed will decrease.

Explanation:

When you ride a roller coaster, the wheels rub/scrape the rails, creating heat as a result of friction. And friction will slow you down. So increasing the friction on a roller coaster would slow it down.

Answer:

B

Explanation:

Friction opposes motion therefore reducing motion

Answer:

42.05 m/s

Explanation:

From the question given above, the following data were obtained:

Initial velocity (u) = 0 m/s

Height (h) = 239 m

Acceleration due to gravity (g) = 3.7 m/s²

Final velocity (v) =?

The velocity with which the camera hits the ground can be obtained as follow:

v² = u² + 2gh

v² = 0² + 2 × 3.7 × 239

v² = 0 + 1768.6

v² = 1768.6

Take the square root of both side

v = √(1768.6)

v = 42.05 m/s

Therefore, the velocity with which the camera hits the ground is 42.05 m/s

Answer:

True

Because mitochondria is the powerhouse of the cell.

Explanation:

Hope this helps you

Answer:

True

Explanation:

Answer:

Eh = 21 [J]

Removed as heat.

Explanation:

This is a case of energy conservation, we have to take into account the energies that go in and out of the system. In this case, 135 [J] of energy are entered in the form of work of the compressor to the chamber where the refrigerant is compressed, now of these 135 [J] 114 [J] were used as internal energy, this internal energy is used to increase the pressure and temperature of the refrigerant.

In this way the rest of the energy of the 135 [J] was lost in the form of heat to determine this loss of energy, we simply perform the arithmetic subtraction.

Eh = 135 - 114 = 21 [J]

Eh = 21 [J]

The pressure at the bottom when the given tank is full of water will be 19600 Pa.

Pressure can be calculated by the formula,

[tex]\bold {P = \rho h g}[/tex]

Where,

P- pressure = ?

[tex]\bold {\rho}[/tex] - density of water = 1000 kg/m²

h - height of water = 2 m

g - gravity acceleration = 9.8 m/s

Put the values in the formula

[tex]\bold {P = 2 \times 1000 \times 9.8} \\\\\bold {P = 19600\ Pa}[/tex]

Therefore, the pressure at the bottom when the given tank is full of water will be 19600 Pa.

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Answer:

Explanation: Gravity keeps our bones and bodily muscles from not working, things like dams can be one example of gravitational energy being used for our benefits. Without gravitational energy, our earth most likely won't stay in it's own atmosphere. Another example is like a car on the top of the hill, or a snow pack (Where an avalanche might happen)

Answer:

Explanation:

ok it's correct

Answer:

So waves are everywhere. But what makes a wave a wave? What characteristics, properties, or behaviors are shared by the phenomena that we typically characterize as being a wave? How can waves be described in a manner that allows us to understand their basic nature and qualities?

A wave can be described as a disturbance that travels through a medium from one location to another location. Consider a slinky wave as an example of a wave. When the slinky is stretched from end to end and is held at rest, it assumes a natural position known as the equilibrium or rest position. The coils of the slinky naturally assume this position, spaced equally far apart. To introduce a wave into the slinky, the first particle is displaced or moved from its equilibrium or rest position. The particle might be moved upwards or downwards, forwards or backwards; but once moved, it is returned to its original equilibrium or rest position. The act of moving the first coil of the slinky in a given direction and then returning it to its equilibrium position creates a disturbance in the slinky. We can then observe this disturbance moving through the slinky from one end to the other. If the first coil of the slinky is given a single back-and-forth vibration, then we call the observed motion of the disturbance through the slinky a slinky pulse. A pulse is a single disturbance moving through a medium from one location to another location. However, if the first coil of the slinky is continuously and periodically vibrated in a back-and-forth manner, we would observe a repeating disturbance moving within the slinky that endures over some prolonged period of time. The repeating and periodic disturbance that moves through a medium from one location to another is referred to as a wave.

Hope That Helps!!

Explanation:

Answer:

6.75m/s

Explanation:

using the second equation of motion, the time is calculated.

and with the formula a= (v - u)/t

where a is acceleration but in this case it's deceleration (and should be negated as you solve it ) .

v is final velocity

u is initial velocity

t is time taken

Answer:

Momentum is a product of mass and velocity.

Explanation:

Hope this helps you

Crown me as brainliest:)

Answer:

92

Explanation:

Answer:

(1) body composition, (2) flexibility, (3) muscular strength, (4) muscular endurance, and (5) cardiorespiratory endurance. 

Answer:

letterman is shooting the kids

We use insulators to avoid being electrocuted. electricians use rubber gloves to avoid shock. Cables are insolated with rubber so you can hold them without getting shocked even if it is plugged in.

Answer:

a) [tex] y_{max} = 7.7 m [/tex]

b) y = 7.4 m

Explanation:

a) La altura máxima que alcanza la pelota se puede encontrar usando la siguiente ecuación:

[tex] y_{max} = y_{0} + v_{0y}t - \frac{1}{2}gt^{2} [/tex]    (1)

En donde:  

[tex]y_{0}[/tex]: es la altura inicial = 0

[tex]v_{0y}[/tex]: es la velocidad inicial en y

g: es la gravedad = 9.81 m/s²

t: es el tiempo

Primero debemos encontrar la velocidad inicial en y:

[tex] v_{fy} = v_{0y} - gt [/tex]

Sabiendo que la velocidad final en y es igual a cero (en la altura máxima), y con t = 1.25 s (la mitad del tiempo total) tenemos:

[tex] v_{0y} = gt = 9.81 m/s^{2}*1.25 s = 12.3 m/s [/tex]

Ahora, podemos encontrar la altura máxima:

[tex] y_{max} = v_{0y}t - \frac{1}{2}gt^{2} = 12.3 m/s*1.25 s - \frac{1}{2}9.81 m/s^{2}*(1.25 s)^{2} = 7.7 m [/tex]

b) Podemos encontrar la altura cuando t = 1 s con la misma ecuación (1):

[tex]y_{max} = y_{0} + v_{0y}t - \frac{1}{2}gt^{2} = 12.3 m/s*1 s - \frac{1}{2}9.81 m/s^{2}*(1 s)^{2} = 7.4 m[/tex]

Por lo tanto, la pelota se encontraba a 7.4 m luego de 1 segundo despúes del lanzamiento.

Espero que te sea de utilidad!      

Answer:

Explanation:

Angle of refraction is the angle made by refracted ray with the normal at the point of incidence . In this figure , refracted ray has been shown by line having arrow-head . Normal has been shown by broken line .

We observe that in figure D , angle made by refracted ray with normal is greatest . So figure D is the answer.

The  image where the angle of refraction is the greatest is the image D

The angle of refraction is the angle that the refracted ray made with the x-axis.

The higher the angle between the refracted ray and the x-axis, the higher the angle of refraction and vice versa.

From the given diagram, we can see that the  image where the angle of refraction is the greatest is the image D

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