Answer:
The toy's energy is 18 J.
Explanation:
We have, a 4 kg toy is lifted off the ground and falls at 3 m/s. It is required to find toy's energy.
The toy will have kinetic energy due to its motion. The energy is given by :
So, the toy's energy is 18 J.
Answer:
A λ = 97.23 nm
, B) λ = 486.2 nm
, C) λ = 53326 nm
Explanation:
With that problem let's use the Bohr model equation for the hydrogen atom
= -k e² /2a₀ 1/n²
For a transition between two states we have
-
= -k e² /2a₀ (1/
² - 1 / n₀²)
Now this energy is given by the Planck equation
E = h f
And the speed of light is
c = λ f
Let's replace
h c / λ = - k e² /2a₀ (1 / ² - 1 / no₀²)
1 / λ = - k e² /2a₀ hc (1 / ² -1 / n₀²)
Where the constants are the Rydberg constant = 1.097 10⁷ m⁻¹
1 / λ = (1 / n₀² - 1 / nf²)
Now we can substitute the given values
Part A
Initial state n₀ = 1 to the final state = 4
1 / λ = 1.097 10⁷ (1/1 - 1/4²)
1 / λ = 1.0284 10⁷ m⁻¹
λ = 9.723 10⁻⁸ m
We reduce to nm
λ = 9.723 10⁻⁸ m (10⁹ nm / 1m)
λ = 97.23 nm
Part B
Initial state n₀ = 2 final state = 4
1 / λ = 1.097 10⁷ (1/2² - 1/4²)
1 / λ = 0.2056 10⁻⁷ m
λ = 486.2 nm
Part C
Initial state n₀ = 3
1 / λ = 1,097 10⁷ (1/3² - 1/4²)
1 / λ = 5.3326 10⁵ m⁻¹
λ = 5.3326 10-5 m
λ = 53326 nm
Answer:
The linear momentum is given by the following equation:
(1)
Where is the mass and
the velocity.
On the other hand, the kinetic energy is given by:
(2)
Which is the same as:
Now, if we double the kinetic energy, equation (2) changes to:
(3)
So, if we want to obtain the kinetic energy as shown in (3), the only option that works is increasing momentum by a factor of or
:
Applying this in (2):
>>>As we can see, this equation is the same as equation (3)
Therefore, the correct answer is B