Answer:
you'll see rocks that have been there for years
Work = force x distance
= 100N (force) x 0.5m (distance)
= 50J
Answer:
26b) 66.7%
27) 500 N
Explanation:
26.a) In a two pulley system, the load is attached to one of the pulleys. The other pulley is attached to a fixed surface, as well as one end of the rope. The other end of the rope goes around moving pulley, then around the fixed pulley.
26.b) Mechanical advantage is the ratio between the forces:
MA = load force / effort force
Efficiency is the ratio between the work:
e = work done on load / work done by effort
Work is force times distance.
e = (F load × d load) / (F effort × d effort)
Rearranging:
e = (F load / F effort) × (d load / d effort)
e = MA × (d load / d effort)
In a two pulley system, the load moves half the distance of the effort. So the efficiency is:
e = (4/3) × (1/2)
e = 2/3
e = 66.7%
27) In a three pulley system, the load moves a third of the distance of the effort.
e = (F load / F effort) × (d load / d effort)
0.40 = (600 N / F) × (1/3)
F = 500 N
Answer: Take your pick
Explanation:
if they are all in parallel 1 /(1/100 + 1/300 + 1/50) = 30 Ω
if 50 is in parallel with 2 in series 1 / (1/(100 + 300) + 1/50) = 44.444...Ω
if 100 is in parallel with 2 in series 1 / (1/(50 + 300) + 1/100) = 77.777...Ω
if 300 is in parallel with 2 in series 1 / (1/(100 + 50) + 1/300) = 100 Ω
If 50 is in series with 2 in parallel 50 + 1/(1/100 + 1/300) = 125 Ω
If 100 is in series with 2 in parallel 100 + 1/(1/50 + 1/300) = 142.857...Ω
If 300 is in series with 2 in parallel 300 + 1/(1/50 + 1/100) = 333.333...Ω
If they are all in series 100 + 300 + 50 = 450 Ω