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3 years ago

What is the meaning of length based on scientific measurements?

Physics

2 answers:

Maksim231197 [3]3 years ago

4 0

Poopie get get vCard can v coming can be v

xxTIMURxx [149]3 years ago

4 0

Answer:

At one time the meter was defined as the distance between 2 lines on a platinum bar (meant to be 1 / 10,000,000) of distance between North Pole and equator)

Nowdays 1 meter = 1,553,163.5 wavelengths of Kr 86 (can be reproduced in any laboratory)

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Two racing boats set out from the same dock and speed away at the same constant speed of 104 km/h for half an hour (0.500 h), th

Zinaida [17]

Answer:

The blue boat traveled 6.1 km farther west than the green boat

The green boat traveled 10.7 km farther south than the blue boat

Explanation:

The equation for linear uniform speed movement is

X(t) = X0 + v * t

Since we have two coordinates (X, Y) we use

X(t) = X0 + vx * t

Y(t) = Y0 + vy * t

The dock will be the origin of coordinates so X0 and Y0 will be zero. The X axis will be pointing west and the Y axis south.

The blue boat moves with a direction 24° south of west, so it will have speeds:

vxb = 104 * cos(24) = 95 km/h

vyb = 104 * sin(24) = 42.3 km/h

And the green boat:

vxg = 104 * cos(37.7) = 82.3 km/h

vyg = 104 * sin(37.7) = 63.6 km/h

After half hour the boats will have arrived at positions

Xb = 95 * 0.5 = 47.5 km

Yb = 42.3 * 0.5 = 21.1 km

And

Xg = 82.3 * 0.5 = 41.4 km

Yg = 63.6 * 0.5 = 31.8 km

The difference in positions of the boats

47.5 - 41.4 = 6.1 km

31.8 - 21.1 = 10.7 km

5 0

3 years ago

A circular 10-turn coil with a radius of 5.0 cm carries a current of 5 A. It lies in the xy plane in a uniform magnetic field =

Tju [1.3M]

Answer:

U = – 0.12J

Explanation:

Given N = 10 turns, I = 5A, r = 5×10-²m

B^ = 0.05 T iˆ+ 0.3 T kˆ

Magnitude of the magnetic field vector B = √(0.05²+0.3²) = 0.304T

Area = πr² = π(5×10-²)² = 7.85×10-³m²

Magnetic moment μ = NIA

μ = 10×5×7.85×10-³ = 0.3925Am²

U = -μ•B = –0.3925×0.304 = –0.12J

The sign is negative because the magnetic moment is aligned with the magnetic field.

3 0

3 years ago

We have seen that the voltage of a concentration cell can be affected by the concentrations of aqueous components and/or tempera

NemiM [27]

Answer:

1) Magnesium metal/magnesium ion

2) Aluminum/aluminum ion

3) Copper metal/copper(l) ion

Explanation:

The activity series is a series that shows the ease of reactivity of substances in an electrochemical cell.

The substances that are higher up in the series are more reactive in electrochemical cells.

Magnesium is the first element in the series that has the most negative redox potential then followed aluminium.

Hence, according to Nernst,

1) Magnesium metal/magnesium ion

2) Aluminum/aluminum ion

3) Copper metal/copper(l) ion

5 0

3 years ago

Stars set about how many minutes earlier each day? A. 8 B. 6 C. 4 D. 2

Furkat [3]

It is c which is four minutes per day

5 0

3 years ago

A comet fragment of mass 1.96 × 1013 kg is moving at 6.50 × 104 m/s when it crashes into Callisto, a moon of Jupiter. The mass o

vredina [299]

Answer:

Recoil speed, $1.17\times 10^{-5}\ m/s$

Explanation:

Given that,

Mass of the comet fragment, $m_1=1.96\times 10^{13}\ kg$

Speed of the comet fragment, $v_1=6.5\times 10^4\ m/s$

Mass of Callisto, $m_2=1.08\times 10^{23}\ kg$

The collision is completely inelastic. Assuming for this calculation that Callisto's initial momentum is zero. So,

$m_1v_1=(m_2+m_2)V$

V is recoil speed of Callisto immediately after the collision.

$V=\dfrac{m_1v_1}{(m_2+m_2)}\\\\V=\dfrac{1.96\times 10^{13}\times 6.5\times 10^4}{(1.96\times 10^{13}+1.08\times 10^{23})}\\\\V=1.17\times 10^{-5}\ m/s$

So, the recoil speed of Callisto immediately after the collision is $1.17\times 10^{-5}\ m/s$

7 0

3 years ago