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3 years ago

Please help will give the brainliest How did humans decide how long a year should be?

Physics

2 answers:

worty [1.4K]3 years ago

5 0

Answer:

The decided by staring at and observing the stars.

Explanation:

scZoUnD [109]3 years ago

3 0

By how long the earth takes to orbit the sun just once. also including the geocentric model.

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What type of bond connects the atoms in a molecule of Carbon dioxide gas (CO2)?

Troyanec [42]

Answer:

Covalent Bond

Explanation:

Covalent Bonds happen when elements in a compound share electrons to exist together in a stable state as in the diagram

7 0

3 years ago

What part of the gun position equipment supports all of the elevating parts of the gun?

BARSIC [14]

The gunstock it’s also called stock or shoulder stock

5 0

4 years ago

A mail carrier parks her postal truck and delivers packages. To do so, she walks east at a speed of 0.80 m/s for 4.0 min, then n

Murljashka [212]

Explanation:

Given that,

She walks in east,

Speed = 0.80 m/s

Time = 4.0 min

In north,

Speed = 0.50 m/s

Time = 5.5 min

In west,

Speed = 1.1 m/s

Time = 2.8 min

(a). We need to calculate the unit-vector velocities for each of the legs of her journey.

The velocity of her in east

$\vec{v_{1}}=0.80\ \hat{x}\ m/s$

$\vec{v_{2}}=0.50\ \hat{y}\ m/s$

$\vec{v_{3}}=1.1\ \hat{-x}\ m/s$

(b). We need to calculate the unit-vector displacements for each of the legs of her journey

Using formula of displacement

$\vec{d_{1}}=v_{1}\times t_{1}$

In east ,

$\vec{d_{1}}=0.80\times4.0\times60$

$\vec{d_{1}}=192\ \hat{x}\ m$

In north,

$\vec{d_{2}}=0.50\times5.5\times60$

$\vec{d_{2}}=165\ \hat{y}\ m$

In west,

$\vec{d_{3}}=1.1\times2.8\times60$

$\vec{d_{3}}=184.8\ \hat{-x}\ m$

(c). We need to calculate the net displacement from the postal truck after her journey is complete

$\vec{d}=\vec{d_{1}}+\vec{d_{2}}+\vec{d_{3}}$

Put the value in the formula

$\vec{d}=192\hat{x}+165\hat{y}+184.8\hat{-x}$

$\vec{d}=7.2\hat{x}+165\hat{y}$

We need to calculate the magnitude of the displacement

$d=\sqrt{(7.2)^2+(165)^2}$

$d=165.16\ m$

The magnitude of the displacement is 165.16 m.

Hence, This is the required solution.

3 0

3 years ago

A car increases from 15 km/s to 45 km/s in 5 seconds. Calculate the average acceleration of the car during these 5 seconds.

Elodia [21]

Answer:

The answer to your question is 6 km/s

Explanation:

Acceleration is a change in velocity with respect to time, its units are m/s² or km/h².

Data

vo = 15 km/h

vf = 45 km/h

t = 5 s

Formula

$a = \frac{vf - vo}{t}$

Substitution

a = (45 - 15) / 5

a = 30 / 5

a = 6 km/s

7 0

4 years ago

Read 2 more answers

Ancient physicists tried to determine the orbits of the planets every night they carefully track the location of the planets and

Olenka [21]

I believe that the answer is descriptive. It would not be experimental because these astronomers cannot in any way manipulate the stars. They are merely observing.

4 0

3 years ago