Answer:
Explanation:
The initial kinetic energy will be increased by the loss of potential energy and be decreased by the work of friction.
½mv₁² = ½mv₀² + mgh - Fd
½70v₁² = ½(70)14² + 70(9.8)(30) - 13(440)
v₁ = 24.9112... ≈ 25 m/s
Answer: The reason weight for average adult is 530N
Explanation: The clearly see this answer, let's convert this weight to kg using F=mg
530=m×9.8
g is a constant of 9.8m/s2
We divide both sides by 9.8 to get
54kg then this weight is reasonable for an average adult.
Weight is a force, and is defined as mass times acceleration. So (g is acceleration and m is mass):
That's your answer.
Answer:
14.9 m /s
Explanation:
n = n° x v /[ v -v (s) ]
n is apparent frequency , n° is source frequency,v is speed of sound and v(s)
speed of source.
2300 = 2200 x 343 / [343 -v(s)]
v (s ) = 14.9 m /s.
Answer:
400 N
Explanation:
Since the steel bar is uniform, its center of mass must be at its geometric center as well, which is at the same spot as the 75kg mass hanging. So the total mass is 75 + 5 = 80 kg.
Suppose g = 10m/s2, we can then calculate the weight of the system:
W = Fg = 80 * 10 = 800 N
As the weight is at the center with 2 ropes supporting on 2 ends, weight should be evenly distributed on each rope. So each rope is subjected to a tension force of
T = 800 / 2 = 400 N