If a beam of light enters one medium from another medium, what quantity does not change?

We all depend on electricity. Most electricity is created by electromagnetic generators at large power plants and distributed th

Anuta_ua [19.1K]

Answer:

1) not so long (maybe an hour or two)

2) access to information through the internet will be most affected if my computer and mobile phone run out of battery power.

3) yes, one should prepare for power outage. This can be done by having a standby alternative source of power like the use of inverters that stores electrical energy in form of chemical energy, and small internal combustion engine powered electric generators.

4) solar panels can be used to draw power from incident sun rays, this power can be stored in an inverter for future use in case of a power outage.

5) energy from the sun is converted into direct current which is then supplied to an accumulator in the opposite direction to its flow of current. When the energy is needed, it can be used directly, or converted to an alternating current. This is achieved by connecting its terminal to the supply. Electric field is generated by flow of ions and electrons within the working chemical (e.g lithium).

Explanation:

8 0

3 years ago

Which describes the relationship between photon energy and the color of light?

Andrew [12]

Photon energy is directly proportional to the frequency of electromagnetic radiation.
(That would also mean that it's inversely proportional to the wavelength.)

So the photon energy increases as you scan the chart of visible colors
moving from the red end of the rainbow to the blue end.

3 0

3 years ago

Read 2 more answers

What is Force & how many types of Force express with example <br><br><br><br>

ehidna [41]

Answer:

The force is pull or push acting on the body which tends to change its state of rest or of motion is called force.

There are two types of force:

1.Contact force

2. Non-Contact

7 0

3 years ago

A freight car with a mass of 10 metric tons is rolling at 108 km/h along a level track when it collides with another freight car

Rufina [12.5K]

Answer:

20 metric tons

Explanation:

Using the Principle of Conservation of Linear Momentum which states that the total momentum of a system is constant in any direction in which no external force acts.

momentum before collision= momentum after collision

mathematically expressed as

m1u1 + m2u2 = m1v1+m2v2 =0

where:

m1= mass of rolling freight car = 10 metric tons = 10Mg

1 ton = 1000kg= 1Mg

u1 =initial velocity of freight car = 108km/h,

m2 = mass of stationary freight car = ?, this the unknown we are finding

u2 = initial velocity of

m2 = 0, because it is at rest,

v1= final velocity of m1,

v2= final velocity of m2

since they move together in the same direction they share a common final velocity as such

v1=v2= 36km/h

substituting valves in expression give

m1u1 + m2u2 = m1v1 + m2v2= 0

10Mgx 108km/hr + m2 x 0 = 10Mg x 36km/h + m2x36km/h

1080( Mg x km/hr) + 0 = 360 (Mg x Km/h) + 36m2 (km/h)

1080 (Mgx km/hr) - 360(Mg x km/h) = 36m2 (km/h)

720(Mg x km/h) = 36m2 (km/h)

divide both side by 36 (km/h) gives

m2 = 20Mg =20 metric tons

3 0

3 years ago

A satellite is in a circular orbit 21000 km above the Earth’s surface; i.e., it moves on a circular path under the influence of

mina [271]

Answer:

(orbital speed of the satellite) V₀ = 3.818 km

Time (t) = 4.5 × 10⁴s

Explanation:

Given that:

The radius of the Earth is 6.37 × 10⁶ m; &

the acceleration of gravity at the satellite’s altitude is 0.532655 m/s

We can calculate the orbital speed of the satellite by using the formula:

Orbital Speed (V₀) = √(r × g)

radius of the orbit (r) = 21000 km + 6.37 × 10⁶ m

= (2.1 × 10⁷ + 6.37 × 10⁶) m

= 27370000

= 2.737 × 10⁷m

Orbital Speed (V₀) = √(r × g)

Orbital Speed (V₀) = √(2.737 × 10⁷ × 0.532655 )

= 3818.215

= 3.818 × 10³

= 3.818 Km

To find the time it takes to complete one orbit around the Earth; we use the formula:

Time (t) = 2 π × $\frac{r}{V_o}$

= 2 × 3.14 × $\frac{2.737*10^7}{3.818*10^3}$

= 45019.28

= 4.5 × 10 ⁴ s

6 0

3 years ago