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3 years ago

Prehistory can be described as _____.

1 answer:

6 0

The in-between period of time when the first man appeared and when man developed a writing system. Or the period of time before man became literate.

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The frequency of violet light is 7.5x10 to the 14th power hertz. What is the wavelength?

Verizon [17]

Wavelength times frequency = speed of light
7.5E14 x wavelength = 300,000 m/s

Wavelength in meters = 300,000 divided by 7.5E14

8 0

3 years ago

Suppose you put an ice cube into a cup of hot tea. In what direction does energy in the form of heat flow? What happens to the i

Semenov [28]

Answer:

The energy flows between the ice and the tea equally. The table below shows the temperatures of several different objects made of the same material.

6 0

3 years ago

A 2 nC point charge is at the origin, and a second 5 nC point charge is on the x-axis at x = 8 m. Find the electric field (magni

dimaraw [331]

Answer:

The magnitude of the electric field is 5.75 N/C towards positive x- axis.

Explanation:

Given that,

Point charge at origin = 2 nC

Second charge = 5 nC

Distance at x axis = 8 m

We need to calculate the electric field at the point x = 2 m

Using formula of electric field

$E=\dfrac{1}{4\pi\epsilon_{0}}(\dfrac{q_{1}}{r_{1}^2}+\dfrac{q_{2}}{r_{2}^2})$

Put the value into the formula

$E=9\times10^{9}\times(\dfrac{2\times10^{-9}}{2^2}+\dfrac{5\times10^{-9}}{(8-2)^2})$

$E=5.75\ N/C$

The direction is toward positive x- axis.

Hence, The magnitude of the electric field is 5.75 N/C towards positive x- axis.

7 0

2 years ago

A car moving with an initial speed v collides with a second stationary car that is one-half as massive. After the collision the

Mashutka [201]

Answer:

4v/3

Explanation:

Assume elastic collision by the law of momentum conservation:

$m_1v = m_1v_1 + m_2v_2$

where v is the original speed of car 1, v1 is the final speed of car 1 and v2 is final speed of car 2. m1 and m2 are masses of car 1 and car 2, respectively

Substitute $m_2 = m_1/2 \& v_1 = v/3$

$m_1v = \frac{m_1v}{3} + \frac{m_1v_2}{2}$

Divide both side by $m_1$ , then multiply by 6 we have

$6v = 2v + 3v_2$

$3v_2 = 4v$

$v_2 = \frac{4v}{3}$

So the final speed of the second car is 4/3 of the first car original speed

5 0

3 years ago

Which of the following is an example of deposition?

Murrr4er [49]

B would be the correct answer

4 0

3 years ago