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2 years ago

Complete the sentences below using the words below, you may use each word more than once

1 answer:

7 0

Decreases, stays the same, increases. The volume decreases because as air is cooled, the individual molecules collectively possess less kinetic energy and the distances between them decrease, thus leading to a decrease in the volume they occupy at a certain pressure (please note that my answer only holds under constant pressure; air, as a gas, doesn't actually have a definite volume). The mass stays the same because physical processes do not create or destroy matter. The law of conservation of mass is obeyed. You're only cooling the air, not adding more air molecules. The density decreases because as the volume decreases and mass stays the same, you have the same mass occupying a smaller volume. Density is mass divided by volume, so as mass is held constant and volume decreases, density increases.

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The bird that migrates the farthest is the Arctic tern. Each year, the Arctic tern travels

Tanzania [10]

Answer: 131.14km per day

Explanation: since the second half of the terns migration takes 122 days we can assume that the full migration would take 244 days. using this we can divide the total distance by the total amount of days it takes (because speed = distance/time) which is 32,000/244, which would be 131.14

8 0

2 years ago

Which means for obtaining hydrogen from water would require the most energy??

Flauer [41]

I think the correct answer would be to electrolyze water (run an electric current through it) to decompose it into hydrogen and oxygen. Assuming 100% efficiency, it is said that it needs about 40kWh per kilogram of water to fully decompose it.

8 0

2 years ago

A rocket-launching vehicle is moving forward at a constant velocity of 5 m/s. a cannon on the vehicle shoots a shell straight up

Readme [11.4K]

For any object thrown upwards where only the force of gravity is acting upon it, uses the following formula for the maximum height attained.

H= v²/2g, where g = 9.81 m/s²

There are two information of velocities are given. However, we use the 20 m/s information because this is the launch velocity. Hence, the solution is as follows:

H = (20 m/s)²/2(9.81 m/s²)
<em>H = 20.4 m</em>

5 0

3 years ago

An infant's toy has a 120 g wooden animal hanging from a spring. If pulled down gently, the animal oscillates up and down with a

Morgarella [4.7K]

Answer:

0.37 m

Explanation:

The angular frequency, ω, of a loaded spring is related to the period, T, by

$\omega = \dfrac{2\pi}{T}$

The maximum velocity of the oscillation occurs at the equilibrium point and is given by

$v = \omega A$

A is the amplitude or maximum displacement from the equilibrium.

$v = \dfrac{2\pi A}{T}$

From the the question, T = 0.58 and A = 25 cm = 0.25 m. Taking π as 3.142,

$v = \dfrac{2\times3.142\times0.25\text{ m}}{0.58\text{ s}} = 2.71 \text{ m/s}$

To determine the height we reached, we consider the beginning of the vertical motion as the equilibrium point with velocity, v. Since it is against gravity, acceleration of gravity is negative. At maximum height, the final velocity is 0 m/s. We use the equation

$v_f^2 = v_i^2+2ah$

$v_f$ is the final velocity, $v_i$ is the initial velocity (same as v above), a is acceleration of gravity and h is the height.

$h = \dfrac{v_f^2 - v_i^2}{2a}$

$h = \dfrac{0^2 - 2.71^2}{2\times-9.81} = 0.37 \text{ m}$

3 0

3 years ago

As additional resistors are connected in series to a constant voltage source, how is the power supplied by the source affected?

Furkat [3]

Answer:

(D) The power supplied by the source decreases.

Explanation:

If additional resistors are connected in series, then the total resistance of the circuit is increased. By the Ohm’s Law, V = iR, the current decreases.

The power supplied by the source is P = i*i*R = i*(i*R). The term in the parenthesis is the voltage of the circuit and is constant. The ‘i’ outside decreases, therefore the power supplied by the source decreases.

7 0

3 years ago

Read 2 more answers