Answer:
the magnitude of the average contact force exerted on the leg is 3466.98 N
Explanation:
Given the data in the question;
Initial velocity of hand v₀ = 5.25 m/s
final velocity of hand v = 0 m/s
time interval t = 2.65 ms = 0.00265 s
mass of hand m = 1.75 kg
We calculate force on the hand F
using equation for impulse in momentum
F × t = m( v - v₀ )
we substitute
F × 0.00265 = 1.75( 0 - 5.25 )
F × 0.00265 = 1.75( - 5.25 )
F × 0.00265 = -9.1875
F = -9.1875 / 0.00265
F = -3466.98 N
Next we determine force on the leg F
Using Newton's third law of motion
for every action, there is an equal opposite reaction;
so, F = - F
we substitute
F = - ( -3466.98 N )
F = 3466.98 N
Therefore, the magnitude of the average contact force exerted on the leg is 3466.98 N
Explanation:
A star is in equilibrium when the pressures inside the star balance out the force of gravity. The pressure is thermal pressure resulting from the fusion reactions taking place in the star's core. A star stays in equilibrium until the supply of hydrogen in the core is depleted.
In a stable star, the gas pressure pushing out from the center is equal with the gravity pulling atoms inward to the center – when these forces are equal, the star is at equilibrium. Once a star reaches equilibrium for the first time, it will start burning (fusing) hydrogen into helium.
Kepler was the one who during the Renaissance, came up with the theory of elliptical planetary orbits around the sun. Up to that time the planetary orbits were assumed to be circular. By using the observations and data of Tycho Brahe, and also using both mathematical and physical (relative to the properties of matter) proofs, he thus used the scientific method to determine the type of orbits. In other words, he used the model that Brahe had worked out and then developed that model into an accurate appraisal of the orbits. This is the scientific method, starting with what is known and doing investigation into what is unknown by studying the material world and basing one's expanded thinking on the new facts unearthed in the process. In the modern world we all use this method, from figuring out why a vacuum cleaner is not functioning to the theory of plate tectonics.
I hope this helped!
Answer:
92.33Hz
Explanation:
A tuba is considered as having one open end and the other end is closed. Then:
f_n = n×v / 4L
so here
Where n = 4
f_4 = 116.5 Hz
116.5 Hz = nv/4L
116.5 Hz = 4v/4L
4×v / 4L = v / L
116.5 Hz = v/L............1
Let's assume the speed of sound is 343 m/s. Then substituting 343 m/s for v in equation 1
116.5 Hz = v/L
116.5 Hz = 343 m/s/L
Making L the subject
116.5 Hz × L = 343 m/s
L = 343m/s / 116.5Hz
= 2.944 m
Add 0.721 m to the length, and
f_4 = 343m/s / (2.944+0.721)m
f_4 = 343m/s ÷ 3.715
= 92.328 Hz
Approximately = 92.33Hz
Hence the new frequency for the 4th harmonic is 92.33Hz
Work = Force * distance
Work = 40N * 10m
Work = 400N