Answer:
Δy = v₀t + (1/2)gt²
where g = 9.81 m/s if the body is moving downwards and g = -9.81 m/s if the body is moving upwards
Explanation:
The general kinematic equation for horizontal displacement is gives as:
Δx = v₀t + (1/2)at²
Where
Δx = change in the x direction
v₀ = initial velocity
t = time
a = acceleration
If the body is vertically instead of horizontally, Δx is changed to Δy
Δy = v₀t + (1/2)at²
For a vertical moving body, the acceleration it experiences is the gravitational accerelation of the earth 'g'
So the equation becomes:
Δy = v₀t + (1/2)gt²
where g = 9.81 m/s if the body is moving downwards and g = -9.81 m/s if the body is moving upwards
Answer:
69.69 g
Explanation:
Evaporation of water will take out latent heat of vaporization. Let the mass of water be m and latent heat of vaporization of water be 2260000 J per kg
Heat taken up by evaporating water
= 2260000 x m J
Heat lost by body
= mass x specific heat of body x drop in temperature
60 x 3500 x .750 ( specific heat of human body is 3.5 kJ/kg.k)
= 157500 J
Heat loss = heat gain
2260000 m= 157500
m = .06969 kg
= 69.69 g
Answer: only the third option. [Vector A] dot [vector B + vector C]
The dot between the vectors mean that the operation to perform is the "scalar product", alson known as "dot product".
This operation is only defined between two vectors, not one scalar and one vector.
When you perform, in the first option, the dot product of any ot the first and the second vectors you get a scalar, then you cannot make the dot product of this result with the third vector.
For the second option, when you perform the dot product of vectar B with vector C you get a scalar, then you cannot make the dot product ot this result with the vector A.
The third option indicates that you sum the vectors B and C, whose result is a vector and later you make the dot product of this resulting vector with the vector A. Operation valid.
The fourth option indicates the dot product of a scalar with the vector A, which we already explained that is not defined.
To solve this problem we will use the concept related to electrons in a box which determines the energy of an electron in that state.
Mathematically this expression is given by,
Where,
m = mass of an electron
h = Planck's constant
n = is the integer number of the eigenstate
L = Quantum well width
The change in energy must be given in state 1 and 2, therefore
Replacing we have:
Therefore the correct answer is C.
