<span>Hello!
We have the following data:
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Time (T) = ? (in minutes)
Power (P) = 3 kW → 3000 W
Energy (E) = 9 MJ → 9000000 J or (W/s)
Formula of the consumption of electric energy:

Solving:




How many minutes can it run for? (<span>Let's convert in minutes)
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1 minute --------- 60 seconds
y minute --------- 3000 seconds

<span>Product of extremes equals product of means
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I hope this helps! =)
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You will have to use this formula:

Final Velocity (V) = 4m/s
Initial Velocity (Vo) = 8m/s
Acceleration (a) = ? m/s^2
Time (t) = 2 secs
Then:
-> 4 = 8 + a x 2
-> 4 - 8 = 2a
-> -4 = 2a
-> a = -4/2
-> a = -2 m/s^2
Ps: It's value is negative because the she was in retrograde motion.
Answer: Her acceleration is -2 m/s^2.
Answer:
t₁ = 0.95 s
Explanation:
In this chaos we must use the definition of Newton's second law
F = m a = m dv / dt
dv = F dt / m
Let's replace and integrate, let's take the upward direction of the plane as positive, the force is positive
dv = ∫ (3 + 2t) dt / m
v = (3 t + 2 t²/ 2) /m
Let's evaluate between the lower limit t = 0 v = -6 ft / s (going down) to the upper limit t = t and v = 0
0 - (-6) = (3 (t- 0) + (t² -0)) / m
t² + 3t -6m = 0
Let's look for the mass
W = mg
m = W / g
m = 20/32
m = 0.625 slug
Let's solve the second degree equation
t² + 3t -3.75 = 0
t = (-3 ± √ (32 + 4 1 3.75)) / 2
t = (-3 ± 4,899) / 2
t₁ = 0.95 s
t₂ = -3.95 s
We take the positive time