Answer:
7.6 s
Explanation:
Considering kinematics formula for final velocity as
Where v and u are final and initial velocities, a is acceleration and s is distance moved.
Making v the subject then
Substituting 8.8 m/s for u, 138 m for s and 2.45 m/s2 for a then
Also, v=u+at and making t the subject of the formula
Substituting 27.45 m/s for v, 8.8 m/s for u and 2.45 m/s for a then
Therefore, it needs 7.6 seconds to travel
I answered the question but it got deleted?? why?
Answer:
a) V = 195.70 m/s
b) f=3.02 × 10⁻⁴ Hz
c) T = 3311.25 seconds
Explanation:
Given:
Wavelength, λ = 646 Km = 646000 m
Distance traveled = 3410 Km = 3410000 m
Time = 4.84 h = 4.84 × 3600 s = 17424 seconds
a) The speed (V) of the wave is given as
V = distance / time
V = 3410000 m/ 17424 seconds
or
V = 195.70 m/s
b) The frequency (f) of the wave is given as:
f = V / λ
f= 195.70 / 646000
f=3.02 × 10⁻⁴ Hz
c) The time period (T) is given as:
T = 1/ f
T = 1/ (3.02 × 10⁻⁴) Hz
T = 3311.25 seconds
Answer:
50 N
Explanation:
Efficiency of a machine can't be more than 1, so I assume you mean 40%. (Remember, efficiency and mechanical advantage are not the same).
Efficiency is the ratio of work out of a system to the work in to the system.
e = Wout / Win
Work is force times distance, so:
e = (Fout × Dout) / (Fin × Din)
Rearranging:
Fin = (Fout × Dout) / (e × Din)
Fin = (Fout / e) × (Dout / Din)
Fin = (Fout / e) / (Din / Dout)
We know that e = 0.40, and Fout = 120 N. Since there are 6 pulleys, we also know that Din/Dout = 6.
F = (120 N / 0.4) / 6
F = 50 N
