40 miles at 20 mph takes 2 hours
180 miles at 60 mph takes 3 hours
<span>Average speed = Total distance / Total time </span>
<span>= (40 + 180) / (2 + 3) </span>
= 220 / 5
= 44
<span>The correct answer is 44 m/s</span>
The type of rock that could contain organic matter is C. Sedimentary. I hope this helps you!!
Answer:
It's not enough.
Explanation:
To be able to separate mixtures into substances we have more methods than just distillation, filtration and evaporation. Certain mixtures cannot be filtered, however by decanting can be separated simpler substances from it. Centrifugation separates solids dispersed in liquids that cannot be separated by filtration. Also, it is necessary to try to separate the substance by the method of chromatography, crystallization, etc.
Have a nice day!
Speed, mass, and acceleration. Acceleration affects the kinetic energy, due to it affecting speed; therefore, the more acceleration, the more of an increase/decrease in kinetic energy.
Answer:
1977.696 J
Explanation:
Given;
Weight of the box = 28.0 kg
Force applied by the boy = 230 N
angle between the horizontal and the force = 35°
Therefore,
the horizontal component of the force = 230 × cosθ
= 230 × cos 35°
= 188.405 N
Coefficient of kinetic friction, μ = 0.24
Force by friction, f = μN
here,
N = Normal force = Mass × acceleration due to gravity
or
N = 28 × 9.81 = 274.68 N
therefore,
f = 0.24 × 274.68
or
f = 65.9232 N
Now,
work done by the boy, W₁ = 188.405 N × Displacement
= 188.405 N × 30
= 5652.15 J
and,
the
work done by the friction, W₂ = - 65.9232 N × Displacement
= - 65.9232 N × 30 m
= - 1977.696 J
[ since the friction force acts opposite to the direction of motion, therefore the workdone will be negative]
