Answer:
b
c
e
h
Explanation:
Note that the swing direction was not giving in the question and direction could be sideways (in a turn) or in a track or both
The question show something in common ...acceleration
So let's look at the statements and pick the correct ones
a is false while b is correct as the train is accelerating
c is correct. The train is accelerating even thou the speed could not be ascertained
d is false and not feasible as the train is accelerating
e is true as the train maybe moving at a constant speed in a circle
f is false. This could be constant velocity in a circle. Same as g (false)
h is true. It's accelerating
Answer:
Explanation:
a)
Ff = μmgcosθ
Ff = 0.28(1600)(9.8)cos(-84)
Ff = 458.9217...
Ff = 460 N
b) ignoring the curves required at top and bottom which change the friction force significantly, especially at the bottom where centripetal acceleration will greatly increase normal forces and thus friction force.
W = Ffd
W = 458.9217(-49.4/sin(-84)
W = 22,795.6119...
W = 23 kJ
c) same assumptions as part b
The change in potential energy minus the work of friction will be kinetic energy.
KE = PE - W
½mv² = mgh - (μmgcosθ)d
v² = 2(gh - (μgcosθ)(h/sinθ))
v = √(2gh(1 - μcotθ))
v = √(2(9.8)(49.4)(1 - 0.28cot84))
v = 30.6552...
v = 31 m/s
Below are the choices that can be found from other source:
a. frequency
b. the Doppler effect
c. the resonance effect
<span>d. intensity
The answer is B.
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Milliliters if you're doing science.
The sun’s energy is most useful to humans after it is converted to chemical energy. Living organisms like humans and animals could not directly utilize the energy from the sun because of lack in organs that would allow photosynthesis. Humans and animals obtain the energy from the sun from the intake of food. These foods contain chemical energy which is obtained from the solar energy of the sun. Plants use solar energy for photosynthesis which converts the energy into chemical energy. Then, animals and humans eat the plants obtaining the chemical energy which can readily processed by the body as compared to solar energy.