When jumping straight down, you can be seriously injured if you land stiff-legged. One way to avoid injury is to bend your knees
upon landing to reduce the force of the impact. A 75-kg man just before contact with the ground has a speed of 4.6 m/s. (a) In a stiff-legged landing he comes to a halt in 2.1 ms. Find the average net force that acts on him during this time. N (b) When he bends his knees, he comes to a halt in 0.09 s. Find the average force now. N (c) During the landing, the force of the ground on the man points upward, while the force due to gravity points downward. The average net force acting on the man includes both of these forces. Taking into account the directions of these forces, find the force of the ground on the man in parts (a) and (b). stiff legged landing N bent legged landing
1 answer:
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Answer:
xmax = 9.5cm
Explanation:
In this case, the trajectory described by the electron, when it enters in the region between the parallel plates, is a semi parabolic trajectory.
In order to find the horizontal distance traveled by the electron you first calculate the vertical acceleration of the electron.
You use the Newton second law and the electric force on the electron:
(1)
q: charge of the electron = 1.6*10^-19 C
m: mass of the electron = 9.1*10-31 kg
E: magnitude of the electric field = 4.0*10^2N/C
You solve the equation (1) for a:
Next, you use the following formula for the maximum horizontal distance reached by an object, with semi parabolic motion at a height of d:
(2)
Here, the height d is the distance between the plates d = 2.0cm = 0.02m
vo: initial velocity of the electron = 4.0*10^6m/s
You replace the values of the parameters in the equation (2):
The horizontal distance traveled by the electron is 9.5cm
Answer:
"h" signifies Planck's constant
Explanation:
In the equation energy E = h X v
The "h" there signifies Planck's constant
Planck's constant is a value, that shows the rate at which the energy of a photon increases/decreases, as the frequency of its electromagnetic wave changes.
It was named after Max Planck who discovered this unique relationship between the energy of a light wave and its frequency.
Planck's constant, "h" is usually expressed in Joules second
Planck's constant =