Answer:
Explanation:
Assuming there is only force in the y-component, the total net force acting on the parachute and the sky diver is:
(1)
Where:
is the drag force acting upwards
is the weight of the sky diver acting downwards, hence with negative sign
Then:
(2) This is the total net force excerted on the system parachute-sky diver, and the fact it is positive means is upwards
Now, according Newton's 2nd Law of Motion the force is directly proportional to the mass and to the acceleration of a body:
(3)
Where is the mass of the diver.
Substituting the known values and finding :
(4)
(5)
Finally:
This is the acceleration of the sky diver. Note it has a positive sign, which means its direction is upwards.
Answer:
Explanation:
Rydberg's formula is used to describe the wavelengths of the spectral lines of chemical elements similar to hydrogen, that is, with only one electron being affected by the effective nuclear charge. In this formula we can find the rydberg constant, knowing the wavelength emitted in the transcision between two energy states, we can have a value of the constant.
Where it is the wavelength of the light emitted, R is the Rydberg constant, Z is the atomic number of the element and are the states where .
In this case we have Z=1 for hydrogen, solving for R:
This value is quite close to the theoretical value of the constant
Answer:
For example, when a person walk
Explanation:
The force of friction is a resistive force that opposes the motion of objects. It is produced by the contact between two surfaces: since the surfaces are not perfectly smooth, there are "microbumps" that cause a resistive force in the relative motion of the two surface.
This force is evident, for example, when we try to push a crate along the floor: as we push forward, there is a resistive force acting in the opposite direction, and this force is the force of friction.
The force of friction is in the direction opposite to the motion of the object, so in general it tends to slow down the motion of the object over the surface.
However, there is a particular case in which instead friction helps in accelerating the object.
This scenario is when a person walks: in fact, the foot of the person pushes against the floor (backward), and as a result, the floor "pushes" forward with the force of friction, which helps therefore the person to move forward. In fact, the force of friction is the force that allows us to walk forward: without the force of friction, we could not walk (think about how difficult it is to walk over an icy surface: this is because the force of friction on an icy surface is almost zero!)
<span>You are given a submerged submarine accelerating upward at 0.325 m/s</span>² and the density of sea water is 1.025x10³ kg/m³. The submarine's average density at this time is 22 kg/m³.
Answer:
The index of refraction varies with frequency or color. Frequency does not change as light travels from one medium to another.
Explanation: