Need help finding the average speed.

Answer:

C) 1.5 A

Explanation:

P = IV

180 W = I (120 V)

I = 1.5 A

Answer:

Explanation:

It is the case of perfectly elastic collision . So we shall apply formula of velocity after collision as follows .

Let  m₁ and m₂ be the mass colliding with velocity u₁ and u₂ and their velocity become v₁ and v₂ after collision .

[tex]v_1=\frac{(m_1-m_2)u_1 }{m_1+m_2)} +\frac{2 m_2u_2}{(m_1+m_2)}[/tex]

Putting the values

[tex]v_1=\frac{ (.30-.80).40 }{( .30+.80)} +\frac{2\times .80\times(-.15) }{(.30+.80 )}[/tex]

= - 0.4 m /s

So direction of .30 kg mass will be reversed .

[tex]v_2=\frac{ ( m_2-m_1) u_2 }{( m_1+m_2)} +\frac{2 m_1u_1}{(m_1+m_2)}[/tex]

putting the values

[tex]v_2=\frac{ ( .80-.30)(-.15) }{( .30+.80)} +\frac{2 \times.30\times.40}{(.30+.80)}[/tex]

= .15 m /s

The direction of .80 kg will become from left to right ie its direction will be reversed .

b ) Minimum amount of kinetic energy will be at the position when they move with common velocity

common velocity

v = .3 x .4 - .8 x .15 / (.3 + .8)

= 0

c )

Missing energy is stored as elastic potential energy in the spring .

Answer:

is the last one, a magnetic wave and electrical current moving in opposite directions

Explanation:

opposite directions always attract in magnetic waves and fields

Answer:

External locus of control

Explanation:

External locus of control is an attitude people possess that makes them attribute their failures or successes to factors other than themselves. The opposite of this type of attitude is the Internal locus of control where the individuals take responsibility for the outcomes of their actions whether good or bad. One good thing about the external locus of control is that when the individuals with this characteristic record successes, they attribute it to others and this presents them as people with team spirit. However, when they record failures, they do not want to take the blame, but rather attribute it to others.

Fred exhibits an external locus of control because he attributed his speeding to other factors like the road signs and GPS instead of fully admitting that it was his fault.

Explanation:

Assuming the 10 m distance is the vertical displacement, the work done by both people is the same.

Work = force × distance

W = (250 N) (10 m)

W = 2500 J

The power of the first person is:

Power = work / time

P = 2500 J / 120 s

P = 20.83 W

The power of the second person is:

P = 2500 J / 60 s

P = 41.67 W

Answer:

K.E of truck > K.E of car

Explanation:

Mass of the truck = 8000Kg

K.E=[tex]\frac{1}{2} mv[/tex]

K.E =[tex]\frac{1}{2}*8000*v\\ 4000v[/tex]

Mass of the car = 1000 Kg

K.E of the car =[tex]\frac{1}{2}*1000*v\\ 500v[/tex]

Therefore Kinetic energy of the truck is greater than that of the car

Answer:

Explanation:

[tex]m =800kg\\v = 15\\\\K.E = \frac{1}{2}mv^2\\ K.E= \frac{1}{2} \times 800\times 15^2\\= 400 \times 225\\= 90000 joules\\= 90 kilojoules[/tex]

Answer:

hypernova making a black hole, and merger of two neutron stars

Answer:

[tex]r = \frac{v}{i} = v = ri \\ i = \frac{v}{r} [/tex]

Answer:

we learned that an object that is vibrating is acted upon by a restoring force. The restoring force causes the vibrating object to slow down as it moves away from the equilibrium position and to speed up as it approaches the equilibrium position. It is this restoring force that is responsible for the vibration. So what forces act upon a pendulum bob? And what is the restoring force for a pendulum? There are two dominant forces acting upon a pendulum bob at all times during the course of its motion. There is the force of gravity that acts downward upon the bob. It results from the Earth's mass attracting the mass of the bob. And there is a tension force acting upward and towards the pivot point of the pendulum. The tension force results from the string pulling upon the bob of the pendulum. In our discussion, we will ignore the influence of air resistance - a third force that always opposes the motion of the bob as it swings to and fro. The air resistance force is relatively weak compared to the two dominant forces.

The gravity force is highly predictable; it is always in the same direction (down) and always of the same magnitude - mass*9.8 N/kg. The tension force is considerably less predictable. Both its direction and its magnitude change as the bob swings to and fro. The direction of the tension force is always towards the pivot point. So as the bob swings to the left of its equilibrium position, the tension force is at an angle - directed upwards and to the right. And as the bob swings to the right of its equilibrium position, the tension is directed upwards and to the left. The diagram below depicts the direction of these two forces at five different positions over the course of the pendulum's path.

that's what I know so far

Answer

As the angle of incidence increases in Figure 2.8, a point is finally reached where the refracted ray does not emerge at the second layer but lie along the interface. This particular angle of incidence at which the angle of refraction is 90° and the refracted ray lies along the interface is known as the critical angle. At and beyond the critical angle, there is no transmitted ray and therefore a very high reflected ray will be recorded .

Therefore,

sinθisin90=Vp1Vp2

But, sin 90 = 1.

At critical angle,

sinθcritical=Vp1Vp2

A critical refracted wave travels along the interface between layers and is refracted back into the upper layer at the critical angle. The waves refracted back into the upper layer are called head waves or first-break refractions because at certain distances from a source, they are the first arriving energy. Recorded first-break refraction is shown in Figure 2.10.

Note that these first-break refractions can give us important information about the shallow velocities on land seismic data.

Note also that seismic data are acquired in such a way that reflections from horizons of interest are in the pre-critical region, even at the farthest offset in the data.

In reality, part of the seismic energy arriving at an interface is transmitted and refracted, and another part of the energy is reflected at that same interface. Given that there are many reflectors in the subsurface, there will be many paths from source to receiver, each of them with a different travel time. The proportion of energy reflected depends on the material properties of the two bounding layers and on the angle of incidence

Answer:

The collapse of a protostar with less than 0.08 times the mass of the Sun is halted by DEGENERACY PRESSURE. b. As a protostar shrinks in size, its central temperature rises along with its THERMAL PRESSURE. c. A star that has not yet finished forming is called a__PROTOSTAR_____. d. A forming star spins more rapidly as it collapses because of conservation of ANGULAR MOMENTUM. e. If a protostar has a mass too small for it to sustain nuclear fusion it becomes the type of object known as a____BROWN DWARF____

Answer:

The impulse exerted by one cart on the other has a magnitude of 4 N.s.

Explanation:

Given;

mass of the first cart, m₁ = 2 kg

initial speed of the first car, u₁ = 3 m/s

mass of the second cart, m₂ = 4 kg

initial speed of the second cart, u₂ = 0

Let the final speed of both carts = v, since they stick together after collision.

Apply the principle of conservation of momentum to determine v

m₁u₁ + m₂u₂ = v(m₁ + m₂)

2 x 3 + 0 = v(2 + 4)

6 = 6v

v = 1 m/s

Impulse is given by;

I = ft = mΔv = m(

The impulse exerted by the first cart on the second cart is given;

I = 2 (3 -1 )

I = 4 N.s

The impulse exerted by the second cart on the first cart is given;

I = 4(0-1)

I = - 4 N.s (equal in magnitude but opposite in direction to the impulse exerted by the first).

Therefore, the impulse exerted by one cart on the other has a magnitude of 4 N.s.

Answer:

The name of the force is elastic (spring) force

Explanation:

The elastic force which is the restoration force of an elastic (spring like) object that tries to return to its initial non-stretched state built up by the pulling of the bow by the archer (using the muscles) pushes on the arrow which the archer releases the same time he leaves the bow string, and the arrow flies in the direction already pointed by the archer

The arrow ultimately falls down due to gravity forces that acts on all objects within the Earths gravitational field. However due to the speed of constant horizontal speed of the arrow and increasing downward speed of the due to the gravity force, the falling of the arrow looks disappointing.

Answer:

its velocity, wavelength and frequency all change

Explanation:

Whenever a wave crosses the boundary between two media of different densities, its velocity, frequency and wavelength changes. This appears as a bending of the wave as it crosses the boundary from one medium to another.

Refraction is a fundamental property of waves. Hence when light is travelling from air into water, it wavelength, speed and frequency all changes at the interface between the two media.

Answer:

speed=330m/s

Explanation:

the speed of wave is given as

speed(meter per second) =frequency(hertz) * wavelength(meters)

so using the above formula we substitute the figures given in the question in the formula we get

speed = 0.4*825

speed =330m/s

note m/s is the si unit for speed which is read as meter per second

therefore speed =330m/s

Answer:

Hey there!

Mixtures are physically combined and can be separated. For example, sand and water is a mixture.

Pure substances are samples of matter with definite, and unchangeable chemical properties. For example, diamond is a pure substance.

Let me know if this helps :)

a pure substance is a substance that has not been mixed with anything, a mixture has been mixed with another substance. an example is

dirt +water=mud iron is an example of a substance

Answer:

The weak force governs the decay of a neutron into a proton (a process known as beta decay). The strong force binds quarks together into protons and neutrons (the residual strong force holds protons and neutrons together in the nucleus). Gravity governs the motion of an apple falling from a tree.

Explanation:

Answer:

Weak Nuclear force

Answer:

8 atm

Explanation:

Ideal gas law:

PV = nRT

where P is pressure, V is volume, n is moles, R is universal gas constant, and T is absolute temperature.

If n is constant:

PV / T = PV / T

(4 atm) (60 L) / (27 + 273) K = P (40 L) / (127 + 273) K

0.8 atm = 0.1 P

P = 8 atm

Answer: Some of the ways to control noise pollution are as follows: (1) Control at Receiver's End (2) Suppression of Noise at Source (3) Acoustic Zoning (4) Sound Insulation at Construction Stages (5) Planting of Trees (6) Legislative Measures.

Answer:

You have to:

a) Improve your insulation.

b) Install a fence

c) Use modern Acoustic wall panels

d) Plant trees

e) Reduce electronic volumes,e.t.c.

Explanation:

okay.

Answer:

1. Tienes 1 kg de fruta.

2. Queda por recorrer 1/4 km.

3. Ambos pesan lo mismo.

Explanation:

1. Tienes 1/2 kg y cuando te doy 1/4 te queda:

[tex] m = \frac{1}{2} - \frac{1}{4} = \frac{1}{4} [/tex]

Ahora cuando te doy 3/4 kg te queda en total:

[tex] m_{T} = \frac{1}{4} + \frac{3}{4} = 1 kg [/tex]

Por lo tanto, tienes 1 kg de fruta al final.

2. Si falta por recorrer la mitad de la mitad, tenemos:

[tex] d = \frac{1/2}{2} = \frac{1}{4} [/tex]

Entonces, queda por recorrer 1/4 km.

3. El peso (P) del hierro es:

[tex] P = m*g [/tex]    

[tex] P = (1 + 1/2)kg*9.81 m/s^{2} = 14.72 N [/tex]

Y el peso de la paja es:

[tex] P = 3/2 kg*9.81 m/s^{2} = 14.72 N [/tex]

Por lo tanto, ambos pesan lo mismo.

Espero que te sea de utilidad!

Answer:

The color blue emerges at 19.16° and the color red emerges at 19.32°.

Explanation:

The angle at which the two colors emerge can be calculated using the Snell's Law:

[tex]n_{1}sin(\theta_{1}) = n_{2}sin(\theta_{2})[/tex]

Where:

n₁ is the refractive index of the incident medium (air) = 1.0003

n₂ is the refractive index of the refractive medium:

    blue light in crown glass = 1.524

    red light in crown glass = 1.512

θ₁ is the angle of the incident light = 30°

θ₂ is the angle of the refracted light                            

For the red wavelengths we have:

[tex] \theta_{2} = arcsin(\frac{n_{1}sin(\theta_{1})}{n_{2}}) = arcsin(\frac{1.0003*sin(30)}{1.512}) = 19.32 ^{\circ} [/tex]

For the blue wavelengths we have:

[tex] \theta_{2} = arcsin(\frac{n_{1}sin(\theta_{1})}{n_{2}}) = arcsin(\frac{1.0003*sin(30)}{1.524}) = 19.16 ^{\circ} [/tex]

Therefore, the color blue emerges at 19.16° and the color red emerges at 19.32°.  

I hope it helps you!

Answer:

Take up space

Explanation:

Actually we know this by the definition of matter which states that "matter is any substance that has mass and takes up space by having volume."

hope it helped you:)

Answer:

integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, and reproductive

Explanation:

and this is biology not physics

Answer:

There will  be a huge problem of holding the wire strands together, and the power losses will also be amplified.

Explanation:

The force per unit length on two current carrying conductors, lying parallel to each other is proportional to the product of the current through the conductors, and inversely proportional to their distance apart. This force is attractive if the current flows through these conductors in the same direction, and is repulsive if it flows in the opposite direction.

For the strand of wire that make up a high voltage wire bundle, there will be a force of attraction pulling the wires closer to each other, and they will experience the maximum pulling force possible, since they lie next to each other. This force helps to hold these wires in a high tension wire strand together, limiting the area, and reducing "skin effect."

In the case that this wires in the wire strand acts in opposite of the known behavior, the wires will repel and push each other apart. This pushing apart will increase power loss due "skin effect" which is increased by an increase in exposed surface area of the wire strands. This will pose a big problem for high tension transmission.

Answer:

x = 27.3 m

Explanation:

This is a projectile launching exercise, let's start by looking for the time it takes for the rock to reach the height of the window.

Let's use trigonometry to find the velocities of the rock

           sin 40 = [tex]v_{oy}[/tex] / v

           cos 40 = v₀ₓ / v

           v_{oy}= v sin 40

           v₀ₓ = v cos 40

           v_{oy} = 30 sin 40 = 19.28 m / s

           v₀ₓ = v cos 40

           v₀ₓ = 30 cos 40 = 22.98 m / s

we look for the time

        [tex]v_{y}^2[/tex] = v_{oy}^2 - 2 g y

         v_{y}^2 = 19.28 2 - 2 9.8 16 = 371.71 - 313.6 = 58.118

        v_{y} = 7.623 m / s

we calculate the time

          v_{y} = v_{oy} - gt

          t = (v_{oy} - v_{y}) / g

          t = (19.28 -7.623) / 9.8

          t = 1,189 s

since the time is the same for both movements let's use this time to find the horizontal distance

           x = v₀ₓ t

           x = 22.98 1,189

           x = 27.3 m

Answer:

This is called restricted speed

Answer:

Transverse wave

Explanation:

Its because in transverse wave the particle displacement is perpendicular to the direction of wave propagation..hope it helps you...

Answer:

The final temperature is 31.94°

Explanation:

The mass of the water in the container m₁ = 200 g = 0.2 kg

The initial temperature of the water,  T₁₁ = 30°C

The mass of the iron, m₂ = 200 g = 0.2 kg

The temperature of the iron T₂₁= 50°C is immersed in the water,

The specific heat capacity of the water, c₁ = 4200 J/(kg·°C)

The specific heat capacity of the iron, c₂ = 450 J/(kg·°C)

Heat capacity relation is given by the formula;

Heat capacity Q = Mass, m × Specific heat capacity, c × Temperature change, (T₂ - T₁)

Given that energy can neither be created nor destroyed, and with the assumption that all the heat lost by the nail is gained by the water we have;

Heat lost by iron nail = Heat gained by the  water

m₁ × c₁ × (T₂ - T₁₁) = m₂ × c₂ × (T₂₁ - T₂)

Where, T₂ is the final temperature

0.2 kg × 4200 J/(kg·°C) × (T₂ - 30) = 0.2 kg × 450 J/(kg·°C) × (50° - T₂)

840·T₂ - 25200 = 4500 - 90·T₂

4500 + 25200 = 840·T₂ + 90·T₂

29700 = 930·T₂

T₂ = 29700/930 = 31.94°.

The final temperature = 31.94°.