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Juliette [100K]
3 years ago
11

9. An object starting with a velocity of 20m/s accelerates to

Physics
1 answer:
Aliun [14]3 years ago
4 0

Answer:

6.25 s

Explanation:

V=u+at

t= (v-u)/a

 = (45-20)/4 = 6.25 s

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Is how high or low sound is
JulsSmile [24]

Answer:

How high the sound or how low the sound is depending on the pitch of the sound which in this case the frequencies of the sound. The higher of the frequencies , the higher of the pitch but it has the shortest length of wave (λ). That's why AM radio have a longer range but bad audio quality than FM radio that have better audio quality with shorter range.

5 0
3 years ago
Calculate the energy of a photon emitted when an electron in a hydrogen atom undergoes a transition from =7 to =1.
Harrizon [31]

1.549×10-19lJ is the energy of a photon emitted when an electron in a hydrogen atom undergoes a transition from =7 to =1.

The equation E= hcE =hc, where h is Planck's constant and c is the speed of light, describes the inverse relationship between a photon's energy (E) and the wavelength of light ().

The Rydberg formula is used to determine the energy change.

Rydberg's original formula used wavelengths, but we may rewrite it using units of energy instead. The result is the following.

aaΔE=R(1n2f−1n2i) aa

were

2.17810-18lJ is the Rydberg constant.

The initial and ultimate energy levels are ni and nf.

As a change of pace from

n=5 to n=3 gives us

ΔE

=2.178×10-18lJ (132−152)

=2.178×10-18lJ (19−125)

=2.178×10-18lJ×25 - 9/25×9

=2.178×10-18lJ×16/225

=1.549×10-19lJ

Learn more about Rydberg formula here-

brainly.com/question/13185515

#SPJ4

8 0
2 years ago
-. A 2kg cart moving to the right at 5m/s collides with an 8kg cart at rest. As a
bulgar [2K]

Answer:

<em>The velocity of the carts after the event is 1 m/s</em>

Explanation:

<u>Law Of Conservation Of Linear Momentum </u>

The total momentum of a system of bodies is conserved unless an external force is applied to it. The formula for the momentum of a body with mass m and speed v is  

P=mv.  

If we have a system of bodies, then the total momentum is the sum of the individual momentums:

P=m_1v_1+m_2v_2+...+m_nv_n

If a collision occurs and the velocities change to v', the final momentum is:

P'=m_1v'_1+m_2v'_2+...+m_nv'_n

Since the total momentum is conserved, then:

P = P'

In a system of two masses, the equation simplifies to:

m_1v_1+m_2v_2=m_1v'_1+m_2v'_2

If both masses stick together after the collision at a common speed v', then:

m_1v_1+m_2v_2=(m_1+m_2)v'

The common velocity after this situation is:

\displaystyle v'=\frac{m_1v_1+m_2v_2}{m_1+m_2}

The m1=2 kg cart is moving to the right at v1=5 m/s. It collides with an m2= 8 kg cart at rest (v2=0). Knowing they stick together after the collision, the common speed is:

\displaystyle v'=\frac{2*5+8*0}{2+8}=\frac{10}{10}=1

The velocity of the carts after the event is 1 m/s

3 0
2 years ago
The latin word (Cirro) mean that the clouds are in high level <br><br> True of false?
Ivahew [28]

Answer:

False

Explanation:

The Latin word "Cirro" means "curly" or "curl of hair" as in a cirrocumulus cloud. Cirrocumulus clouds are wispy clouds, and while they do appear high in the sky, the word "cirro" does not mean high in level.

Therefore, the answer is False.

Have a lovely rest of your day/night, and good luck with your assignments! ♡

6 0
3 years ago
Read 2 more answers
A motor uses motion in a magnetic field to produce an electric current. true or false
irinina [24]

Well, that's a nice, concise description, but it applies to a
generator, not a motor.  A motor does exactly the opposite.
It uses an electric current to produce motion in a magnetic field.

Sadly, the statement is false.

5 0
3 years ago
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