A cart is pushed ahead for 3.5 s with a force of 360 N. Determine the change in momentum of the cart.

On a cosmic calendar, in which the history of the universe is compressed into one year, how long is the average human life span?

netineya [11]

Answer:

If one were to use 5 billion years as the age of the universe and 75 years as the average human life span then

T = 75 / 5 E9 = 1.5E-8

The number of seconds in a year is 3600 * 24 * 365 = 3.2E7

If t = N * T seconds in a year * fraction of human life span

t = 1.5E-8 * 3.2E7 = .48

A human life span is about 1/2 second compared to the life of the universe if the universe were compressed to a single year

8 0

2 years ago

Which will have the lowest density A) Ice B) Steam C) water

Nesterboy [21]

Answer:

steam will have the lowest density.

Hope it will help :)

4 0

3 years ago

If you hit another object with your vehicle, your _____ will be slowed or stopped by the force of impact caused by that object u

konstantin123 [22]

The answer is the vehicle. At the precise moment of the impact in a collision, there is the release of energy when a vehicle strikes another vehicle or another object. Earlier to an impact, a vehicle and everything inside the vehicle is traveling at whatever speed the vehicle had been going. As the collision continues, the vehicle slowly loses energy. However, the vehicle occupants and any others items in the vehicle continue to move forward at the same speed as the vehicle had been traveling prior to impact.

7 0

4 years ago

A sheet of glass is coated with a 500-nm-thick layer of oil (n = 1.42).

tamaranim1 [39]

Answer:

a) 473.33 nm 

b) 568 nm and 406 nm

c) bluish green and blue

Explanation:

a) As the light traverses the layer of oil it first reflects at the front surface of the oil. Here the index of refraction increases from that of air to that of the oil , so a phase change occurs. The light then reflects from the rear surface of oil. The index of refraction increases from that of the oil to that of the glass , so again a phase change occurs. Thus two phase changes occur.

In thin-film interference with 0 or 2 phase changes, condition for constructive interference is:

2t=mλ/n

So:

λ= 2tn/m

For m=1

λ=1420 nm

For m=2

λ=710 nm

For m=3

λ=473.33 nm

For m=4

λ=355 nm

Thus the only wavelength in the visible spectrum (400 - 700 nm) that will give constructive interference is 473.33 nm 

b)

In thin-film interference with 0 or 2 phase changes, condition for destructive interference is:

2t=(m+1/2)λ/n=(2m+1)*λ/2n

so;

λ=4tn/(2m+1)

For m=1

λ=946.667 nm

For m=2

λ=568 nm

For m=3

λ=405.33 nm

For m=4

λ=315.56 nm

Thus the wavelengths in the visible spectrum (400 to 700 nm) that will give destructive interference are 568 nm and 406 nm

c) The color of reflected light is bluish green since the wavelength is 473.3 nm . We know that the colors of reflected and transmitted light are complimentary to each other.Thus the color of transmitted light is blue (due to the combination of wavelengths 568 nm (green) and 406 nm (deep violet).

5 0

4 years ago

What causes earthquakes? Where do earthquakes begin?

Alexandra [31]

The "mantle," or layer of the earth under the crust, is composed of hot, molten rock. The temperature of the molten rock in the mantle is not consistent since it is less hot at the surface ("crust") and more hot towards the core as you move closer to the earth's center ("core").

The hotter molten rock near the core is "bigger"—less dense—than the colder rock near the crust because heat causes stuff to expand. As a result, the hotter (lighter) rock in the core tends to rise while the more dense (heavier) rock farther up tends to sink. As a result, the mantle's molten rock is in motion. It descends from the surface down into the middle, where it heats up, expands, rises back to the surface, then cools down and sinks once again. Convection currents are the patterns of molten rock movement in the mantle. The mantle's convection currents take the shape of circular patterns, causing sideways motion in addition to up and down motion.

The crust of the planet is divided into what are referred to as "plates" at its outermost point. These plates are floating on the mantle, but due to the mantle's sideways motion caused by convection currents, the plates floating on top also desire to move. This plate-moving force is also responsible for the formation of mountain ranges and earthquakes. One plate may be attempting to travel in a different direction from the other plate if there are limits between them. They might be advancing on one another, retreating from one another, or gliding past one another.

Mountain ranges are gradually formed when two plates move nearer one another. Oceans are low basins that are gradually formed as a result of two plates sliding apart from one another. Additionally, earthquake faults like the San Andreas fault in California are created when two plates jostle against one another.

An earthquake is a phenomena that causes the earth's surface to suddenly shift, either as a result of volcanic activity or the release of energy that has built up in a fault.

The definition makes it clear that the majority of earthquakes take place near plate borders, which are the intersections of two tectonic plates. Most earthquakes happen in a seismic zone called the Pacific Ring of Fire. As a result of the collision of two tectonic plates, the Ring of Fire is home to around 81 percent of the greatest earthquakes ever recorded. Additionally, here is where the majority of volcanic activity takes place. The epicenter is the point on the earth's surface that is directly above the hypocenter, which is where the earthquake begins under the surface. Foreshocks can occur during an earthquake.

7 0

2 years ago

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