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4 years ago

15

An airport has runways only 198 m long. a small plane must reach a ground speed of 39 m/s before it can become airborne. what av

erage acceleration must the plane's engines provide if it is to take off safely from its airport? answer in units of m/s 2 .

1 answer:

Anarel [89]4 years ago

8 0

S: 198 m
v=39 m/s
u=0
t=?
a=?

v²=u²+2as
(39)²=(0)²+2(a)(198)
1521=396a
1521/396=a
3.84 m/s^2 = a

Hope I helped :)

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What is the relationship between the center of gravity and the support base for an object that is in stable equilibrium?

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Answer:

when the center of gravity is within the washing area, the torque returns in the body to its initial position and is in a stable equilibrium

Explanation:

The concept of center of gravity is equivalent to the concept of center of mass, in this place all external forces applied can be considered.

When we analyze the balance of a body that is the torque it is the one that defines the balance

τ = F xd

If the torque tends to restore the body to the initial position the balance is stable, but if the torque has to increase the body's rotation the balance is unstable

. When the body tends to rotate the torque with respect to the pivot point at the base it decreases because the distance from the center of gravity to the end of the base decreases in value, but it has to return it to the initial position, the balance is stable. The critical point of this process is when the center of gravity is at the limit of the body base area in this case the torque is zero; If the body rotates a little more the center of gravity is outside the base, the torque changes sign and has to increase the turn, going to an unstable balance.

In summary, when the center of gravity is within the washing area, the torque returns in the body to its initial position and is in a stable equilibrium.

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3 years ago

Determine the wavelengths for Potassium (violet, λ = 400 nm) and Strontium (red, λ = 700 nm) light emissions. Calculate the freq

TEA [102]

Answer:

For Potassium:

Frequency = 7.5 x 10¹⁴ Hz; E (energy) = 8.83 x 10⁻²¹ J

For Strontium:

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Explanation:

Wavelength is represented by λ, and Frequency is represented by ν .

E (energy) = hν = hc/λ, where ν = frequency; c = speed of light = 3 x 10⁸ m/s; 1 s-1 = 1 Hz

h = planck's constant = 6.62 x 10⁻³⁴ J.s; 1 nm = 10⁻⁹ m

1. Potassium λ (wavelength) = 400 nm, Frequency, ν is given by :

ν = c/λ = (3 x 10⁸ m/s) / 400 nm

= (3 x 10⁸ m/s) / 400 x 10⁻⁹ s-1

= 0.0075 x 10¹⁷s-1

= 7.5 x 10¹⁴ s-1

Frequency = 7.5 x 10¹⁴ Hz

E (energy) = hν = (6.62 x 10⁻³⁴ J.s) x (7.5 x 10¹⁴s-1)

E (energy) = 8.83 x 10⁻²¹ J

2. Strontium λ (wavelength) = 700 nm ,Frequency, ν is given by :

ν = c/λ = (3 x 10⁸ m/s) / 700 nm

= (3 x 10⁸ m/s) / 700 x 10⁻⁹s-1

= 0.00428571428 x 10¹⁷s-1

= 4.3 x 10¹⁴ s-1

Frequency = 4.3 x 0¹⁴ Hz

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Read 2 more answers

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Similarly, v is directly proportional to square root of tension. So if we increase tension , velocity also increases. So option e ) is correct.

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4 years ago

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3 years ago