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3 years ago

Why are unit of length mass and time independent with each other?

1 answer:

4 0

Масса (килограмм), длина (метр) и время (секунда) - это 3 из 7 основных единиц в системе СИ.

Базовые единицы произвольно определены как то, что они есть, поэтому они не могут быть получены.

Все другие единицы в системе СИ являются производными от 7 основных единиц, таких как скорость (метр / секунда).

Остальные 4 - это температура (Кельвин), количество вещества (моль), электрический ток (ампер) и светимость (кандела).

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What is the calculation for elastic potential?

grin007 [14]

Elastic potential energy is equal to the force times the distance of movement. Elastic potential energy = force x distance of displacement. Because the force is = spring constant x displacement, then the Elastic potential energy = spring constant x displacement squared.

3 0

3 years ago

You have a set of calipers that can measure thicknesses of a few inches with an uncertainty of ± 0.005 inches. You measure the t

Bond [772]

Answer:

a) x = (0.0114 ± 0.0001) in , b) the number of decks is 5

Explanation:

a) The thickness of the deck of cards (d) is measured and the thickness of a card (x) is calculated

x = d / 52

x = 0.590 / 52

x = 0.011346 in

Let's look for uncertainty

Δx = dx /dd Δd

Δx = 1/52 Δd

Δx = 1/52 0.005

Δx = 0.0001 in

The result of the calculation is

x = (0.0114 ± 0.0001) in

b) You want to reduce the error to Δx = 0.00002, the number of cards to be measured is

#_cards = n 52

The formula for thickness is

x = d / n 52

Uncertainty

Δx = 1 / n 52 Δd

n = 1/52 Δd / Δx

n = 1/52 0.005 / 0.00002

n = 4.8

Since the number of decks must be an integer the number of decks is 5

3 0

3 years ago

A particle leaves the origin with a speed of 3 106 m/s at 38 degrees to the positive x axis. It moves in a uniform electric fiel

Salsk061 [2.6K]

Answer:

If the particle is an electron $E_y = 3.311 * 10^3 N/C$

If the particle is a proton, $E_y = 6.08 * 10^6 N/C$

Explanation:

Initial speed at the origin, $u = 3 * 10^6 m/s$

$\theta = 38^0$ to +ve x-axis

The particle crosses the x-axis at , x = 1.5 cm = 0.015 m

The particle can either be an electron or a proton:

Mass of an electron, $m_e = 9.1 * 10^{-31} kg$

Mass of a proton, $m_p = 1.67 * 10^{-27} kg$

The electric field intensity along the positive y axis $E_y$ , can be given by the formula:

$E_y = \frac{2 m u^2 sin \theta cos \theta}{qx} \\$

If the particle is an electron:

$E_y = \frac{2 m_e u^2 sin \theta cos \theta}{qx} \\$

$E_y = \frac{2 * 9.1 * 10^{-31} * (3*10^6)^2 *(sin38)( cos38)}{1.6*10^{-19} * 0.015} \\$

$E_y = 3311.13 N/C\\E_y = 3.311 * 10^3 N/C$

If the particle is a proton:

$E_y = \frac{2 m_p u^2 sin \theta cos \theta}{qx} \\$

$E_y = \frac{2 * 1.67 * 10^{-27} * (3*10^6)^2 *(sin38)( cos38)}{1.6*10^{-19} * 0.015} \\$

$E_y = 6.08 * 10^6 N/C$

8 0

3 years ago

An airplane flies from Houston to New York City, which is a distance of 2280 kilometers. The trip takes 3.5 hours. What was the

garik1379 [7]

Answer:

a)603 km/hr

Explanation:

7 0

2 years ago

As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff springs arr

Natalija [7]

Answer:

a) F = 680 N, b) W = 215 .4 J , c) F = 1278.4 N

Explanation:

a) Hooke's law is

F = k x

To find the displacement (x) let's use the elastic energy equation

$K_{e}$ = ½ k x²

k = 2 $K_{e}$ / x²

k = 2 85.0 / 0.250²

k = 2720 N / m

We replace and look for elastic force

F = 2720 0.250

F = 680 N

b) The definition of work is

W = ΔEm

W = $K_{ef}$ - $K_{eo}$

W = ½ k ( $x_{f}$ ² - x₀²)

The final distance

$x_{f}$ = 0.250 +0.220

$x_{f}$ = 0.4750 m

We calculate the work

W = ½ 2720 (0.47² - 0.25²)

W = 215 .4 J

We calculate the strength

F = k $x_{f}$

F = 2720 0.470

F = 1278.4 N

6 0

3 years ago

Why are unit of length mass and time independent with each other?​

Why are unit of length mass and time independent with each other?