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3 years ago

An observer notices that 12 waves pass by in 4 seconds. What is the frequency of these waves? 0.33 Hz 16 Hz 48 Hz 3 Hz

Physics

1 answer:

Dennis_Churaev [7]3 years ago

8 0

Answer:

Frequency = 3 Hz

Explanation:

Frequency is a measure of Hertz. Recall that Hertz is the unit expressing cycles/second, where one second is the denominator of the fraction for simplicity. If there are 12 waves every four seconds, and one wave represents one cycle, dividing 12 waves by 4 seconds will give the answer of 3 waves (or cycles) per one second.

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Explain the relationship between force, mass and acceleration in Newton's second law

Nikitich [7]

Newton's second law of motion describes what happens to a body when an external force is applied to it.

Newton's second law of motion states that the force acting on an object is equal to the mass of that object times its acceleration. In mathematical form this is written as

F = ma

Where F is force , m is mass and a is acceleration. The math or logic behind this is that if you double the force, you double the acceleration, but if you double the mass, you cut the acceleration in half.

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3 years ago

The distance between two charged objects is doubled. What happens to the electrostatic force between the two?a)It will double.b)

zzz [600]

Answer:

d) It will be cut to a fourth of the original force.

Explanation:

The magnitude of the electrostatic force between the charged objects is

$F=k\frac{q_1 q_2}{r^2}$

where

k is the Coulomb's constant

q1 and q2 are the charges of the two objects

r is the separation between the two objects

In this problem, the initial distance is doubled, so

r' = 2r

Therefore, the new electrostatic force will be

$F=k\frac{q_1 q_2}{(r')^2}=k\frac{q_1 q_2}{(2r)^2}=\frac{1}{4}(k\frac{q_1 q_2}{r^2})=\frac{1}{4}F$

So, the force will be cut to 1/4 of the original value.

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3 years ago

An electric travel blanket uses a car's 12V supply. The current is 3A.

snow_lady [41]

For electrical devices . . .

   Power dissipated = (voltage) x (current) =

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3 years ago

A ball is thrown into the air with an upward velocity of 20 feet per second. Its height, h, in feet after t seconds is given by

Margarita [4]

Thank you for posting your question here at brainly. Feel free to ask more questions.
The best and most correct answer among the choices provided by the question is B. Reaches a max height of 8.25 feet after 0.63 seconds . 

Hope my answer would be a great help for you.

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3 years ago

Which of the physical variables listed below will change when you change the area of the capacitor plates (while keeping the bat

RSB [31]

Answer:

a. Capacitance

b. Charge on the plates

e. Energy stored in the capacitor

Explanation:

Let A be the area of the capacitor plate

The capacitance of a capacitor is given as;

$C = \frac{Q}{V} = \frac{\epsilon _0 A}{d} \\\\$

where;

V is the potential difference between the plates

The charge on the plates is given as;

$Q = \frac{V\epsilon _0 A}{d}$

The energy stored in the capacitor is given as;

$E = \frac{1}{2} CV^2\\\\E = \frac{1}{2} (\frac{\epsilon _0 A}{d} )V^2$

Thus, the physical variables listed that will change include;

a. Capacitance

b. Charge on the plates

e. Energy stored in the capacitor

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3 years ago