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
The answer is:
C. 361 m/s
The explanation:
To calculate the speed of sound at a given temperature (50°C) we are going to use this formula:
v = 331 + 0.6T
when V is the velocity
and T is the temperature = 50°C
by substitution:
v = 331 + 0.6(50)
v = 361 m/s
So, The correct answer is C.
because of the variation of the motion of the molecules of air with change of temperature so, the velocity (V) of the sound in the air is change with temperature.
Answer:
film is at distance of 3.07 cm from lens
Explanation:
Given data
focal length = 3.06 cm
distance = 10.4 m = 1040 cm
to find out
How far must the lens
solution
we apply here lens formula that is
1/f = 1/p + 1/q
here f = 3.06 and p = 1040 so we find q
1/f = 1/p + 1/q
1/3.06 = 1/1040 + 1/q
1/ q = 0.3258
q = 3.0690 cm
so film is at distance of 3.07 cm from lens
Answer:
1.9841256 kg
Explanation:
Given;
Length of the swimming pool = 25.0 ft = 7.62 m ( 1 ft = 0.3048 m )
Width of the swimming pool = 18.5 ft = 5.64 m
Depth of the pool = 9.0 ft =
Total depth of the water in the pool when filled = 9 ft - 7 inches = 2.56 m
now,
Volume of the water in the pool = Length × Width × Depth
or
Volume of the water in the pool = 7.62 × 5.64 × 2.56 = 110.2292 m³
also,
1 m³ = 1000 L
thus,
110.2292 m³ = 110229.2 L
also it is given that 18 mg of Cl is added to 1 liter of water
therefore,
In 110229.2 L of water Cl added will be = 110229.2 × 18 = 1984125.6 mg
or
= 1.9841256 kg
Answer:
Explanation:
The general consensus is that it's more “natural” to define distance (meter) and time (second) and as base units, and derive velocity a the ratio between them. ... The general consensus is that it's more “natural” to define distance (meter) and time (second) and as base units, and derive velocity a the ratio between them.
