Answer:
A
Explanation:
Let the x represent the amount of heat generated from the fossil fuel.
88% of x = 0.88 x
0.88 x was used to convert water to steam.
heat carried by steam = 40% × 0.88 x = 0.352 x
efficiency of the heat -to- work conversion = work output / work input = 0.352 x / x = 0.352 × 100 = 35.2 % which is less than 40 %
<h2>
Density of the unknown liquid is 771.93 kg/m³</h2>
Explanation:
An empty graduated cylinder weighs 55.26 g
Weight of empty cylinder = 55.26 g = 0.05526 kg
Volume of liquid filled = 48.1 mL = 48.1 x 10⁻⁶ m³
Weight of cylinder plus liquid = 92.39 g = 0.09239 kg
Weight of liquid = 0.09239 - 0.05526
Weight of liquid = 0.03713 kg
We have
Mass = Volume x Density
0.03713 = 48.1 x 10⁻⁶ x Density
Density = 771.93 kg/m³
Density of the unknown liquid is 771.93 kg/m³
Answer:
12.5 m/s
Explanation:
The motion of the hammer is a free fall motion, so a uniformly accelerated motion, therefore we can use the following suvat equation:

Where, taking downward as positive direction, we have:
s = 8 m is the displacement of the hammer
u = 0 is the initial velocity (it is dropped from rest)
v is the final velocity
is the acceleration of gravity
Solving the equation for v, we find the final velocity:

So, the final speed is 12.5 m/s.
Answer:
yes
Explanation:
this is simple
the horizontal line is adjacent
the vertical line is opposite
recall that cos x=adj/hyp
adj=hyp(cos x)
while opp=hyp(sin x)
<h2>
Speed of motorboat is 36 km/hr and speed of current is 4 km/hr.</h2>
Explanation:
Let speed of motor boat be m and speed of current be c.
A motorboat traveling with a current can go 160 km in 4 hours.
Distance = 160 km
Time = 4 hours
Speed = m + c
We have
Distance = Speed x Time
160 = (m+c) x 4
m + c = 40 --------------------- eqn 1
Against the current it takes 5 hours to go the same distance.
Distance = 160 km
Time = 5 hours
Speed = m - c
We have
Distance = Speed x Time
160 = (m-c) x 5
m - c = 32 --------------------- eqn 2
eqn 1 + eqn 2
2m = 40 + 32
m = 36 km/hr
Substituting in eqn 1
36 + c = 40
c = 4 km/hr
Speed of motorboat is 36 km/hr and speed of current is 4 km/hr.